The Karasu (Kazakh: Қарасу; Russian: Карасу) is a river in Karkaraly District, Karaganda Region, Kazakhstan.

[1] The Karasu is one of the longest rivers flowing into endorheic lake Karasor.

The nearest inhabited place is Koyandy village, 5 kilometres (3.1 mi) to the southeast of the river's mouth.

[1] The Karasu has its sources in the southern slopes of the highest part of the Zheltau Massif, central Kazakh Uplands, at the border of Pavlodar Region.

In its middle course it bends westwards and in this last stretch it flows roughly parallel to the Taldy to the south.