Leonard Brook is a 3.39 mi (5.46 km) long first-order tributary to Tunungwant Creek.

[2] Leonard Brook rises about 3 miles (4.8 km) east of Limestone, New York in Cattaraugus County and then flows northwest, west, and north to meet Tunungwant Creek about 1.5 miles (2.4 km) north of Limestone, New York.

Leonard Brook drains 4.01 square miles (10.4 km2) of area, receives about 43.8 in/year (111 cm/year) of precipitation, and is about 85.18% forested.