The Dwaar Kill is a 17-mile-long (27 km)[1] tributary of the Wallkill River that drains a 28-square-mile (73 km2) area[2] of Orange and Ulster counties in the U.S. state of New York.

Like the Wallkill and the Shawangunk, which also has a tributary named the Dwaar Kill, it flows in a northeastern direction toward the Hudson River via Rondout Creek.

Continuing northeast, it flows past the former hamlet of Searsville, where early settlers built mills to tap its power.

A short distance north of that crossing, it turns toward the east, taking it just south of Shawangunk Grasslands National Wildlife Refuge.

Albany Post Road (Ulster County Route 9) crosses, and then the Dwaar flows past the Crowell brick works.