Kotlovyna (until 1948: Bolboka; Ukrainian: Котловина; Gagauz: Bolboka; Romanian: Bulboaca, formerly Bolboca and Cotlovina) is a selo in Izmail Raion of the southern Ukrainian oblast of Odesa.

[1] Kotlovyna is situated on the western bank of Lake Yalpuh.

According to the 2001 Ukrainian census, 86.72% of the village population spoke Gagauz.

Until 18 July 2020, Kotlovyna belonged to Reni Raion.

This article about a location in Odesa Oblast is a stub.