The Rohachyk river (Ukrainian: Рогачик) is a left tributary of the Dnieper river in Kherson oblast, Ukraine.

It names derives from a Ukrainian word for the "horn" as the river is winding.

It flows through the territory of Kakhovka Raion of Kherson Oblast.

The mouth area of the river 7 km in length creates Nyzhniy (Lower) Rohachyk estuary which is separated from the Dnieper by Kakhovka Reservoir dam.

The river flows through such settlements as: Verkhnii Rohachyk, Novooleksiivka, Trudovyk, Zoria, Heorhiivka, Oleksiivka, Prolatarii.