Brownville is a town in Jefferson County, New York, United States. The population was 6,263 at the 2010 census, up from 5,839 in 2000. The town is named after Jacob Brown, an early settler and leader.

Brownville is located in the western part of the county, northwest of Watertown. The town contains a village also named Brownville.

The Oneida people were the original inhabitants of the area.^{[citation needed]}

The town was settled around 1799 near Brownville village. It was one of the first towns in the county. Its name is derived from the founder and first settler, Jacob Brown, who was a major-general in the United States Army and is considered to be a heroic figure in the War of 1812.

The town was formed in 1802 from the town of Leyden while still part of Herkimer County.

Many of the northern towns of the county were established, or partly established, from parts of Brownville, including Le Ray (1806), Lyme (1818), Pamelia (1819), Orleans (1821), and Alexandria (1821).

In 1828, the community of Brownville set itself off from the town by incorporating as a village.

In 1855, the community of Dexter set itself off from the town by incorporating as a village.