Oz Academy Openweight Championship

The Oz Academy Openweight Championship is a women's professional wrestling championship owned by the Oz Academy promotion. The reigning champion is referred to as the "Wizard of Oz".^[1] The championship, which is situated at the top of Oz Academy's championship hierarchy, was introduced on March 10, 2007, when Aja Kong defeated Chikayo Nagashima in the finals of a tournament to become the inaugural champion.^[2]

Oz Academy Openweight Championship
Current design of the championship (2019 – present)
Details
Promotion	Oz Academy
Date established	October 23, 2006[1]
Current champion	Saori Anou
Date won	April 13, 2025
Statistics First champion Aja Kong[2] Most reigns Mayumi Ozaki (4 reigns) Longest reign Akino (537 days) Shortest reign Mio Shirai (4 hours, 2 minutes) Oldest champion Mayumi Ozaki (55 years, 183 days) Youngest champion Yoshiko (24 years, 95 days) Heaviest champion Aja Kong (103 kg (227 lb)))[3] Lightest champion Chikayo Nagashima (52 kg (115 lb)))[4]

Reigns

Aja Kong was the first champion in the title's history.^[2] She also holds the records for most reigns, with three.^[2][5][6] Akino holds the record for the longest reign, at 537 days, achieved on her first reign. Mio Shirai's only reign of four hours and two minutes^[7] is the shortest in the title's history. Overall, there have been twenty-nine reigns shared among eighteen different wrestlers. Mio Momono is the current champion in her first reign.

Title history

Key

No.	Overall reign number
Reign	Reign number for the specific champion
Days	Number of days held
Defenses	Number of successful defenses
+	Current reign is changing daily

No.	Champion	Championship change			Reign statistics			Notes	Ref.
		Date	Event	Location	Reign	Days	Defenses
1	Aja Kong	March 10, 2007	Queen Rebirth	Tokyo, Japan	1	309	1[8]	Kong defeated Chikayo Nagashima in the finals of a five-woman tournament to become the inaugural champion.	[2]
2	Carlos Amano	January 13, 2008	The Wizard of OZ 2008	Tokyo, Japan	1	364	2[9]		[8]
3	Mayumi Ozaki	January 11, 2009	The Wizard of OZ 2009	Tokyo, Japan	1	42	2[10]		[9]
4	Dynamite Kansai	February 22, 2009	The Country of OZ 2009	Tokyo, Japan	1	175	0[5]		[11]
5	Aja Kong	August 16, 2009	Plum Hanasaku ~ Country of OZ 2009	Tokyo, Japan	2	36	0[12]		[5]
6	Manami Toyota	September 21, 2009	OZ-Power is Everything - night 1	Sapporo, Hokkaido, Japan	1	93	0[13]		[12]
7	Carlos Amano	December 23, 2009	here is No Christmas in the Country of OZ!	Tokyo, Japan	2	200	1[14]		[13]
8	Kaoru	July 11, 2010	Summer Factor	Tokyo, Japan	1	273	4[6]		[14]
—	Vacated	April 10, 2011	—	—	—	—	—	The championship was vacated, when Kaoru suffered an injury and was unable to continue a three-way street fight against Aja Kong and Mayumi Ozaki, forcing the match to be ended in a no contest.	[6]
9	Aja Kong	April 10, 2011	One Night in Heaven	Tokyo, Japan	3	19	0[15]	Kong defeated Mayumi Ozaki to win the vacant championship.	[6]
10	Ran Yu-Yu	April 29, 2011	Heavenly Days in Osaka	Osaka, Japan	1	86	0[16]		[15]
11	Dynamite Kansai	July 24, 2011	Gravity	Tokyo, Japan	2	28	0[17]		[16]
12	Mayumi Ozaki	August 21, 2011	Plum Hanasaku ~ Country of OZ 2011 - night 2: 15th Anniversary ~ Yokohama Dreams Park	Yokohama, Kanagawa, Japan	2	217	0[18]	This was a four-way elimination match, also involving Aja Kong and Shinobu Kandori.	[17]
13	Chikayo Nagashima	March 25, 2012	A Kingdom of the Chaos	Tokyo, Japan	1	395	2[19]	This was a Dress Up Wild Fight 30-minute Time of the Trial match.	[18]
14	Akino	April 24, 2013	Wednesdays Showdown	Tokyo, Japan	1	537	7[20]		[19]
15	Tsubasa Kuragaki	October 13, 2014	No Answer	Tokyo, Japan	1	216	2[21]		[22]
16	Akino	May 17, 2015	Reincarnation - night 2	Tokyo, Japan	2	21	0[23]		[21]
17	Mio Shirai	June 7, 2015	Focus - night 1	Tokyo, Japan	1	<1	0		[23]
—	Vacated	June 7, 2015	Ozabun Spin-off	Tokyo, Japan	—	—	—	Mio Shirai vacated the championship due to losing to Kaho Kobayashi in a non-title match.	[7][24]
18	Sonoko Kato	August 23, 2015	Plum Hanasaku ~ Country Of OZ 2015: Yokohama Dreams Park #3	Yokohama, Kanagawa, Japan	1	245	5[25]	Kato defeated Hiroyo Matsumoto in a Last Woman Standing match to win the vacant championship. The match started off as a six-woman elimination tag team match, where Kato, Akino and Tsubasa Kuragaki faced Matsumoto, Arisa Nakajima and Hikaru Shida.	[23]
—	Vacated	April 24, 2016	The Artist	Tokyo, Japan	—	—	—	Kato was stripped of the championship after her title defense against Hiroyo Matsumoto ended in a no contest.	[25]
19	Sonoko Kato	July 18, 2016	Aja Kong 30th Anniversary ~ Summer Jumbo Kotobuki	Tokyo, Japan	2	118	1[26]	Kato defeated Mayumi Ozaki in a No Holds Barred Hardcore match to win the vacant championship.	[27]
20	Hiroyo Matsumoto	November 13, 2016	OZ Academy 20th Anniversary ~ Yokohama Dreams Park DK	Yokohama, Kanagawa, Japan	1	350	3[28]		[26]
21	Yoshiko	October 29, 2017	Yokohama Undersea Unexplored Expedition	Yokohama, Kanagawa, Japan	1	217	4		[28]
22	Hikaru Shida	June 3, 2018	Rude in June	Tokyo, Japan	1	315	2		[29]
23	Mayumi Ozaki	April 14, 2019	It is the Dawn of the Era	Tokyo, Japan	3	721	4		[30]
24	Sonoko Kato	April 4, 2021	OZ Academy Silver Bullet	Tokyo, Japan	3	70	1[31]		[32]
25	Kaori Yoneyama	June 13, 2021	OZ Academy The End Of Bright	Tokyo, Japan	1	35	1		[33]
26	Maya Yukihi	July 18, 2021	OZ Academy Tournament 25th Fortress	Nagoya, Japan	1	<1	0		[34]
—	Vacated	July 18, 2021	—	—	—	—	—
27	Maya Yukihi	August 18, 2021	OZ Academy Plum No Hanasaku OZ No Kuni ~ Mayumi Ozaki Debut 35th Anniversary	Tokyo, Japan	2	228	1	This was a four-way match, also involving Mayumi Ozaki, Saori Anou and Yumi Ohka.	[35]
28	Akino	April 3, 2022	OZ Academy Battle Big Bonus In Korakuen	Tokyo, Japan	3	644	6		[36]
29	Mio Momono	January 7, 2024	OZ Academy The Wizard Of OZ 2024	Tokyo, Japan	1	112	0		[37]
30	Mayumi Ozaki	April 28, 2024	OZ Academy Battle Big Bonus 2024	Tokyo, Japan	4	182	3	This was a winner takes all match which was also contested for Ozaki's AAAW Single Championship.	[38]
31	Ryo Mizunami	October 27, 2024	OZ Academy at Yokohama Budokan 2024	Tokyo, Japan	1	168	1	The winner of the Yokohama Budokan Tournament Kyoto Ranbu got to challenge for the title.	[39]
32	Saori Anou	April 13, 2025	OZ Academy Battle Big Bonus 2025	Tokyo, Japan	1	121+	0		[40]

Combined reigns

Three-time champion Akino, who is the longest combined-reigning champion at 1,202 days.

As of August 12, 2025.

†	Indicates the current champion

Rank	Wrestler	No. of reigns	Combined defenses	Combined days
1	Akino	3	13	1,202
2	Mayumi Ozaki	4	9	1,172
3	Carlos Amano	2	3	564
4	Sonoko Kato	3	7	433
5	Chikayo Nagashima	1	2	395
6	Aja Kong	3	1	364
7	Hiroyo Matsumoto	1	3	350
8	Hikaru Shida	1	2	315
9	Kaoru	1	4	273
10	Maya Yukihi	2	1	228
11	Yoshiko	1	4	217
12	Tsubasa Kuragaki	1	2	216
13	Dynamite Kansai	2	0	203
14	Ryo Mizunami	1	1	168
15	Saori Anou †	1	0	121+
16	Mio Momono	1	0	112
17	Manami Toyota	1	0	93
18	Ran Yu-Yu	1	0	86
19	Kaori Yoneyama	1	1	35
20	Mio Shirai	1	0	<1