| Island's Name | Island group(s) | Country/Countries |
|---|
|
| Ma Wan |  Hong Kong |  China |
| Maadhiguvaru | Gaafu Alif Atoll |  Maldives |
| Machias Seal | Disputed Between  Maine and  New Brunswick | Disputed between
 United States and  Canada |
| Mackay |  North Carolina and  Virginia | United States |
| Mackenzie King | Queen Elizabeth Islands,  Nunavut and  Northwest Territories | Canada |
| Mackinac | Lake Huron,  Michigan | United States |
| Maclellan | Tennessee River,  Tennessee | United States |
| Macquarie | Southern Ocean,  Tasmania |  Australia |
| Madagascar | Indian Ocean |  Madagascar |
| La Maddalena |  Sardinia |  Italy |
| Iles des Madeleines | |  Senegal |
| Madeline | Lake Superior,  Wisconsin | United States |
| Madeira |  Madeira |  Portugal |
| Madrid Bar | Mississippi River,  Kentucky | United States |
| Madura | East Java |  Indonesia |
| Maewo | Pacific Ocean |  Vanuatu |
| Mafia | Tanzanian Spice Islands |  Tanzania |
| Isla Magdalena |  Baja California Sur |  Mexico |
| Magerøya | Nordkapp, Finnmark |  Norway |
| Mageshima | Ōsumi Islands part of the Satsunan Islands group of the Ryukyu Islands |  Japan |
| Magusaiai | Shortland Islands |  Solomon Islands |
| Maiao | Windward Islands, Society Islands,  French Polynesia |  Overseas Lands of France |
| Mainau | Lake Constance |  Germany |
| Mainland |  Shetland Islands |  Scotland |
| Main Station | Lake Huron,  Ontario | Canada |
| Majorca |  Balearic Islands |  Spain |
| Majuli[1] | Brahmaputra River, Assam |  India |
| Majuro | Ratak Chain |  Marshall Islands |
| Makada | Duke of York Islands |  Papua New Guinea |
| Makanrushi | Kuril Islands,  Sakhalin Oblast |  Russia |
| Makatea |  Tuamotus, French Polynesia | France |
| Makema | Tuamotus, French Polynesia | France |
| Makura | Shepherd Islands | Vanuatu |
| Malakula | New Hebrides | Vanuatu |
| Malcolm |  British Columbia | Canada |
| Malden | Line Islands |  Kiribati |
| Mal Grad | Lake Prespa |  Albania |
| Mallard | Lake Audubon,  North Dakota | United States |
| Malo | Pacific Ocean | Vanuatu |
| Maloelap Atoll | Ratak Chain | Marshall Islands |
| Malpelo | |  Colombia |
| Malta | Maltese islands |  Malta |
| Makronisos | |  Greece |
| Mamula | Adriatic Sea |  Montenegro |
| Man | Ontario | Canada |
| Mana | Porirua Harbour |  New Zealand |
| Manda | Lamu Archipelago |  Kenya |
| Mandø | North Frisian Islands |  Denmark |
| Mangaia | Cook Islands |  Cook Islands |
| Manhattan |  New York | United States |
| Manihi | King George Islands, Tuamotus, French Polynesia | France |
| Manihiki | Cook Islands | Cook Islands |
| Manilaid | Gulf of Riga |  Estonia |
| Manitou | Lake Superior, Michigan | United States |
| Manitou | Apostle Islands, Wisconsin | United States |
| Manitoulin | Lake Huron, Ontario | Canada |
| Manoel | Maltese islands | Malta |
| Mansel | Nunavut | Canada |
| Manuae | Cook Islands | Cook Islands |
| Manuae | Leeward Islands, Society Islands, French Polynesia | French Polynesia |
| Manus | Admiralty Islands | Papua New Guinea |
| Maple | Mississippi River,  Missouri | United States |
| Ilha de Marajó | |  Brazil |
| Marawah, United Arab Emirates | Persian Gulf |  United Arab Emirates |
| Mare |  California | United States |
| Maréchal | Beira Baixa islands | Portugal |
| Marettimo | Aegadian Islands | Italy |
| Isla Margarita | Nueva Esparta |  Venezuela |
| Margitsziget | Danube River |  Hungary |
| Maria | Tasmania | Australia |
| Maria Cleofas | Islas Marías,  Nayarit | Mexico |
| Maria Madre | Islas Marías, Nayarit | Mexico |
| Maria Magdalena | Islas Marías, Nayarit | Mexico |
| Marie-Galante |  Guadeloupe, Lesser Antilles | France |
| Marinduque | Luzon |  Philippines |
| Marinha Nova | Beira Litoral islands | Portugal |
| Mark | Lake Winnipesaukee,  New Hampshire | United States |
| Marmara | Marmara Islands |  Turkey |
| Marrowstone | Puget Sound,  Washington | United States |
| Marsh |  Louisiana | United States |
| Marshall | Maine | United States |
| Martha's Vineyard |  Massachusetts | United States |
| Martin | Louisiana | United States |
| Ilhas Martin Vaz | Atlantic Ocean | Brazil |
| Martinhal | Algarve islands | Portugal |
| Martinique | Lesser Antilles | France |
| Martuska-sziget | Danube River | Hungary |
| Masbate Island | Masbate | Philippines |
| Maskali | |  Djibouti |
| Masnedø | | Denmark |
| Mason | Mississippi River, Missouri | United States |
| Mason's | Mystic River,  Connecticut | United States |
| Massey | Queen Elizabeth Islands, Nunavut | Canada |
| Matadouce | Beira Litoral islands | Portugal |
| Matagorda |  Texas | United States |
| Mataiva | Palliser Islands, Tuamotus, French Polynesia | France |
| Matakana | Bay of Plenty | New Zealand |
| Mataso | Shepherd Islands | Vanuatu |
| Mathraki | Ionian Islands | Greece |
| Matia | San Juan Islands, Washington | United States |
| Matinicus | Maine | United States |
| Matiu | Wellington Harbour | New Zealand |
| Maatsukyer | Maatsuyker Island Group, Tasmania | Australia |
| Matsu | Lienchang County |  Republic of China |
| Matty | Nunavut | Canada |
| Matua | Kuril Islands, Sakhalin Oblast | Russia |
| Matureivavao | Acteon Group, Tuamotus, French Polynesia | France |
| Maupiti | Windward Islands, Society Islands, French Polynesia | Overseas Lands of France |
| Maud | Marlborough Sounds | New Zealand |
| Maui | Hawaiian Islands,  Hawaii | United States |
| Mauke | Cook Islands | Cook Islands |
| Mauritius | Mascarene Islands |  Mauritius |
| Maurice Island | |  Latvia |
| Maury | Puget Sound, Washington | United States |
| Mausinsel | Bavaria,  Bavaria | Germany |
| Maxwell | Georgian Bay Ontario | Canada |
| Mayne | Gulf Islands, British Columbia | Canada |
| Mayor | Bay of Plenty | New Zealand |
| Mayotte | Comoros archipelago | France |
| Mazaki | |  Cyprus |
| McCallum | Lake Huron, Ontario | Canada |
| McCauley | British Columbia | Canada |
| McCormicks | Susquehanna River,  Pennsylvania | United States |
| McCoy | Georgian Bay Ontario | Canada |
| McCoy | Mississippi River,  Illinois | United States |
| McEvers | Illinois River, Illinois | United States |
| McLaren | Georgian Bay Ontario | Canada |
| McNeil | Puget Sound, Washington | United States |
| McQuade | Georgian Bay Ontario | Canada |
| McQueens |  Georgia | United States |
| Isle of Meadows | New York | United States |
| Medny | Komandorski Islands,  Alaska | Owned by the United States, controlled by Russia |
| Meganisi | Ionian Islands | Greece |
| Mehetia | Windward Islands, Society Islands, French Polynesia | Overseas Lands of France |
| Meighen | Queen Elizabeth Islands, Nunavut | Canada |
| Mejit | Ratak chain | Marshall Islands |
| Melbourne | Nunavut | Canada |
| Mele | Melanesia | Vanuatu |
| Mellum | East Frisian Islands | Germany |
| Melville | Queen Elizabeth Islands, Nunavut and Northwest Territories | Canada |
| Melvin | Lake Winnipesaukee, New Hampshire | United States |
| Memmert | East Frisian Islands | Germany |
| Mendicant | Barataria Bay, Louisiana | United States |
| Merasheen |  Newfoundland and Labrador | Canada |
| Mercer | Lake Washington, Washington | United States |
| Mercury | | New Zealand |
| Merelava | Banks Islands | Vanuatu |
| Merig | Banks Islands | Vanuatu |
| Metinic | Maine | United States |
| Metoma | Torres Islands | Vanuatu |
| Michigan | Lake Superior, Wisconsin | United States |
| Michipicoten | Lake Superior, Ontario | Canada |
| Middle Andaman | Andaman Islands | India |
| Middle Bass | Bass Islands,  Ohio | United States |
| Middle Brewster | Boston Harbor, Massachusetts | United States |
| Middle Duck | Lake Huron, Ontario | Canada |
| Middle Ground | Mississippi River,  Mississippi | United States |
| Middle Ground Coastal Battery | Maharashtra | India |
| Middle | Lake Erie, Ontario | Canada |
| Middle | Ohio River,  West Virginia | United States |
| Middle | Nightingale Islands,  Tristan da Cunha |  British overseas territory of Saint Helena, Ascension and Tristan da Cunha |
| Midgarth | Orkney Islands | Scotland |
| Mikurajima | Izu Islands | Japan |
| Mile | Lake Winnipesaukee, New Hampshire | United States |
| Mili Atoll | Ratak Chain | Marshall Islands |
| Mill | Nunavut | Canada |
| Mill Creek | Ohio River, West Virginia | United States |
| Mill Rock | New York | United States |
| Milos | Cyclades | Greece |
| Mimami daitō | Daitō Islands part of the Ryukyu Islands | Japan |
| Minami Kojima | Senkaku Islands | Disputed by Japan and China |
| Mindanao | Mindanao group | Philippines |
| Minicoy | Lakshadweep | India |
| Minister | Lake Winnipesaukee, New Hampshire | United States |
| Mink | Georgian Bay Ontario | Canada |
| Mink | Lake Winnipesaukee, New Hampshire | United States |
| Minna | Miyako Islands part of the Sakishima Islands part of the Ryukyu Islands | Japan |
| Minnicognashene | Georgian Bay Ontario | Canada |
| Menorca | Balearic Islands | Spain |
| Minquiers | Channel Islands |  Jersey |
| Minu | Persian Gulf |  Iran |
| Mioko | Duke of York Islands | Papua New Guinea |
| Miserable | Rice Lake, Illinois | United States |
| Mishka | Danube River |  Bulgaria |
| Miskan | Persian Gulf |  Kuwait |
| Misool | Raja Ampat Islands | Indonesia |
| Mistaken | Lake Abitibi, Ontario | Canada |
| Mitchell | Louisiana | United States |
| Mitchell Key | Louisiana | United States |
| Mitiaro | Cook Islands | Cook Islands |
| Mitkof | Alexander Archipelago, Alaska | United States |
| Mitraha | Lake Tana |  Ethiopia |
| Miyakejima | Izu Islands | Japan |
| Miyakojima | Miyako Islands part of the Sakishima Islands part of the Ryukyu Islands | Japan |
| Mjältön | High Coast |  Sweden |
| Mljet | Adriatic Sea |  Croatia |
| Mo-do-Meio | Beira Litoral islands | Portugal |
| Mohácsi-sziget | Danube River | Hungary |
| Mohawk | Lake Erie, Ontario | Canada |
| Mohéli | Comoros |  Comoros |
| Mohni | Gulf of Finland | Estonia |
| Moho Tani | Marquesas Islands | French Polynesia |
| Île-aux-Moines | Gulf of Morbihan | France |
| Moínho | Alentejo islands | Portugal |
| Mokoia | Lake Rotorua | New Zealand |
| Molara | | Italy |
| Molène | Archipel de Molène | France |
| Molokai | Hawaii | United States |
| Møn | | Denmark |
| Moneron | Strait of Tartary, Sakhalin Oblast | Russia |
| Monhegan | Maine | United States |
| Monkey | Louisiana | United States |
| Monocanock | Susquehanna River, Pennsylvania | United States |
| Monomoy | Massachusetts | United States |
| Mont Saint-Michel | Normandy | France |
| Monte Branco | Alentejo islands | Portugal |
| Monte Farinha | Beira Litoral islands | Portugal |
| Montecristo | Tuscan Archipelago | Italy |
| Montreal | Hochelaga Archipelago | Canada |
Montserrat  | Leeward Islands of the Lesser Antilles | Overseas territory of the United Kingdom |
| Monument | Shepherd Islands | Vanuatu |
| Moodie | Nunavut | Canada |
| Moon | Georgian Bay Ontario | Canada |
| Moorea | Windward Islands, Society Islands, French Polynesia | Overseas Lands of France |
| Mopelia | Windward Islands, Society Islands, French Polynesia | Overseas Lands of France |
| Moresby | Haida Gwaii, British Columbia | Canada |
| Morfil | River Senegal | Senegal |
| Morgan | Louisiana | United States |
| Morraceira | Beira Litoral islands | Portugal |
| Morris | Charleston Harbor,  South Carolina | United States |
| Mors | Limfjorden | Denmark |
| Mortland | Illinois River, Illinois | United States |
| Moruroa | Tuamotus, French Polynesia | France |
| Moscos Islands | Tanintharyi Region |  Burma |
| Mosenthein | Mississippi River, Illinois | United States |
| Moser | Mississippi River, Missouri | United States |
| Moskenesøya | Lofoten | Norway |
| Moso | Shepherd Islands | Vanuatu |
| Mosterøy | Stavanger Municipality, Ryfylke Islands, Rogaland county | Norway |
| Mota | Banks Islands | Vanuatu |
| Mota Lava | Banks Islands | Vanuatu |
| Motiti | Bay of Plenty | New Zealand |
| Motu One | Windward Islands, Society Islands, French Polynesia | Overseas Lands of France |
| Motuihe | Hauraki Gulf | New Zealand |
| Motukaramarama | Motukawao Islands, Hauraki Gulf | New Zealand |
| Moturata | Mouth of the Taieri River | New Zealand |
| Moturua | Motukawao Islands, Hauraki Gulf | New Zealand |
| Motutapu | Hauraki Gulf | New Zealand |
| Motuwi | Motukawao Islands, Hauraki Gulf | New Zealand |
| Moucha | | Djibouti |
| Moul of Eswick | Shetland Islands | Scotland |
| Mount Ao | Zhoushan Archipelago | China |
| Mount Desert | Maine | United States |
| Mount Maji | Zhoushan Archipelago | China |
| Mousa | Shetland Islands | Scotland |
| Mouse | Bermuda |  Bermuda |
| Mouse | Lake Erie, Ohio | United States |
| Moutoa | Whanganui River | New Zealand |
| Mowat | Georgian Bay (Parry Sound), Ontario | Canada |
| Muck | Inner Hebrides | Scotland |
| Muckle Green Holm | The North Isles,  Orkney Islands | Scotland |
| Muckle Flugga | Shetland Islands | Scotland |
| Muckle Ossa | Shetland Islands | Scotland |
| Muckle Roe | Shetland Islands | Scotland |
| Mud | Detroit River, Michigan | United States |
| Mud Grass | Louisiana | United States |
| Mud Island Shoal | Delaware River, Pennsylvania | United States |
| Muharraq | Persian Gulf |  Bahrain |
| Muhu | West Estonian archipelago; Baltic Sea | Estonia |
| Isla Mujeres | Caribbean,  Quintana Roo | Mexico |
| Muifuiva | Haʻapai |  Tonga |
| Mukawwar | |  Sudan |
| Mulberry | James River, Virginia | United States |
| Mull | Inner Hebrides | Scotland |
| Mumfort | York River, Virginia | United States |
| Murano | Venetian Lagoon,  Veneto | Italy |
| Murphy | Allegheny River, Pennsylvania | United States |
| Murray | Torres Strait Islands,  Queensland | Australia |
| Murry | Thousand Islands, New York | United States |
| Murter | Adriatic Sea | Croatia |
| Musholm | Islands of the Great Belt | Denmark |
| Muskeget | Massachusetts | United States |
| Muskingum | Ohio River, West Virginia | United States |
| Mussau | St. Matthias Islands | Papua New Guinea |
| Mussel Rock | California | United States |
| Mustang | Port Aransas, Texas | United States |
| Mustapha | Ohio River, West Virginia | United States |
| Myingun Island | Rakhine State | Burma |
| Mykines |  Faroe Islands | Denmark |
| Mykonos | Cyclades | Greece |
