Rio San Juan Río San Juan
Location
Country	Mexico
State	Coahuila, Nuevo León, Tamaulipas
Physical characteristics
Source	Coahuila
Mouth	Rio Grande
• location	near Camargo, Tamaulipas
• coordinates	26°21′55″N 98°51′15″W / 26.36528°N 98.85417°W / 26.36528; -98.85417
Basin size	33,538 km2 (12,949 sq mi)[1]
Discharge
• location	IBWC station 08-4642.00, near Camargo[1]
• average	10.4 m3/s (370 cu ft/s)[1]
• minimum	0 m3/s (0 cu ft/s)
• maximum	3,250 m3/s (115,000 cu ft/s)

The San Juan River is the largest and most important river in the Mexican state of Nuevo León. The river feeds the El Cuchillo Dam, which provides the city of Monterrey with water. The San Juan River basin has a total surface area of 33,538 square kilometres (12,949 sq mi).^[1] The San Juan River is a tributary to the Rio Grande (Rio Bravo) — which is the fourth largest river basin in North America. It begins in Coahuila, flows through Nuevo León and into Tamaulipas, where it finally joins the Rio Grande near Camargo, Tamaulipas.

• List of rivers of Mexico
• List of tributaries of the Rio Grande
• San Juan River (Colorado River)