Itkul () is a lake in Chulymsky District, Novosibirsk Oblast, Russian Federation.
The lake is located to the southeast of Chulym, the district capital.
Itkul lies in the Baraba Lowland, West Siberian Plain and belongs to the Chulym river basin. It is the largest lake of Chulymsky District. The lake is elongated from east to west and has two lobes, a western one and an eastern one. They are connected to each other by a wide sound. The eastern wing is about five times larger than the western one.
River Chulym flows to the north. Lake Sektinskoye lies to the east, Kargan to the northwest, Ubinskoye in the same direction, and Inder to the southwest.