The Syniukha (Ukrainian: Синюха) is a river in Ukraine, a left tributary of the Southern Bug, the basin of Black Sea.

It flows into the Southern Bug at Pervomaisk.

[1] It is believed that in the mid-14th century one of the major battles between the Grand Duchy of Lithuania and the Ulus Jochi, the Battle of Blue Waters, took place here.

[2] The Kohutivka Reserve [uk] of national importance is by the Yatran village, at the confluence of Yatran River and Syniukha.

[3] This article related to a river in Ukraine is a stub.