The Lyevaya Lyasnaya (Belarusian: Левая Лясная) is a river in western Belarus.

The Lyasnaya is a right-bank tributary of the Bug River northwest of Brest.

The Lyevaya Lyasnaya flows through Pruzhany Raion and Kamenets Raion areas of Brest Voblast of Belarus.

The river flows through: Mylnisk, Kamyanyets, Vuglyany.

This article related to a river in Belarus is a stub.