Doirani is a town and former municipality in the Kilkis regional unit, Greece. Since the 2011 local government reform it is part of the municipality Kilkis, of which it is a municipal unit. It is situated on the shores of Doiran Lake, which marks the border between Greece and North Macedonia. The municipal unit has an area of 81.213 km2. It had a population of 1,022 according to the 2021 census. It is the Greek part of the former municipality of Doyuran, which was divided in 1913 by the new borders created between Greece and what was then Serbia. The part on the other side of the border is called Dojran. The name comes from the ancient name Doviros.