Koktinkoli (Kazakh: Көктіңкөлі; Russian: Коктинколи) is a lake in Shet District, Karaganda Region, Kazakhstan.

The western shore is steep, lined with cliffs up to 2 meters (6 ft 7 in) high, and consists of gray sandstone mixed with clay.

An earthen dam was built to regulate the water level at the northern and northeastern end, where the river flows in and out.

Koktinkoli does not dry in the summer, but its level fluctuates around 1.5 meters (4 ft 11 in) yearly, depending on the inflow of river Zhaman Sarysu.

Among the fishes living in the lake, the crucian carp, perch, bream and pike deserve mention.