Oktyabrsky () is a rural locality (a settlement) and the administrative center of Oktyabrsky Selsoviet, Kulundinsky District, Altai Krai, Russia. The population was 1,263 as of 2013. There are 15 streets.
Oktyabrsky lies in the Kulunda Steppe, near lake Shchekulduk to the south. It is located 5 km west of Kulunda (the district's administrative centre) by road. Kulunda is the nearest rural locality.