The Kalaus (Russian: Калаус) is a north-flowing river on the Black Sea-Caspian Steppe of southern Russia, in Stavropol Krai.

It is 436 kilometres (271 mi) long, and has a drainage basin of 9,700 square kilometres (3,700 sq mi).

[1] It is a tributary of the Manych.

Formerly, when it reached the Manych, part of its waters would flow east and part west.

Today a low dam blocks flow into the east Manych.