The Lampasas River (lam-PA-sis) is a river in the U.S. state of Texas. The river originates near the city of Hamilton and travels southeast for seventy-five miles through central Texas to a man-made reservoir called Stillhouse Hollow Lake. The river flows approximately 100 miles southeast through Lampasas, Burnet, and Bell Counties. It continues for a short distance after the lake to converge with the Leon River to form the Little River (Texas) near Belton.
The Lampasas river is the northernmost and westernmost river in the natural range of the American Alligator, which is still found there. In June 2015, 2 men were arrested for shooting and killing an alligator that they found on the river.