Nyagak river is a river of West Nile, Northern Uganda.

The Nyagak river runs through Zombo District and Arua District. It is a tributary of the Ora River, which it joins east of the town of Okollo.

Several hydropower developments are located on the Nyagak river :

• Nyagak Power Station
• Nyagak II Power Station
• Nyagak III Power Station