River Izhora, in English also known as River Inger, is the main tributary to River Neva on its run through Ingria in western-most Russia from Lake Ladoga to Gulf of Finland. The small town Ust-Izhora ("mouth of Izhora") is situated at the confluence of Izhora and Neva, halfway between Saint Petersburg and Schlisselburg. The river is noted as the furthest Swedish forces ever reached between the Viking Age and the Time of Troubles.

Izhora's calculated length is only 76 kilometers. The river draws its water mainly from natural groundwater springs, snow melt, and rain water. The river has a sustainable underground water supply in both summer and winter, never drying up or freezing through.