The Tromyogan () is a river in Khanty-Mansi Autonomous Okrug, Russia, a tributary of the Ob. It is long, and has a drainage basin of .
The Tromyogan is a right tributary of the Ob river. It has its sources in the Siberian Uvaly. The river flows to the north of the Vatinsky Yogan basin.
The main tributary of the Tromyogan is the long Agan on the right.