Canyon Lake is a reservoir on the Guadalupe River in the Texas Hill Country in the United States.

The reservoir serves to provide flood control and water supply for the communities downstream from the dam.

It is located in northern Comal County, Texas, on the northeastern fringe of the San Antonio-New Braunfels MSA.

A record flood in July 2002 overtopped the spillway by more than seven feet (2 m) and caused significant damage below Canyon Dam.

GBRA built a hydroelectric facility at Canyon Dam in August 1987; it was put into service in February 1989.

The Corps of Engineers built and maintains eight park areas around the lake for camping, swimming, boating and picnicking.

Hike, bike and equestrian trails are available, as is limited hunting (archery only) and professional fishing guide services.

Plans by GBRA to sell water from Canyon Lake to supply the fast-growing San Antonio and Austin regions have raised concerns that the lake will fall well below the established conservation pool level, potentially causing problems ranging from erosion and weakening of Canyon Dam to a decline in property values and possible health issues from the exposure of long-submerged land.