Vallecito Wash is a wash part of Vallecito Creek, a tributary stream of Carrizo Creek, in San Diego County, California.

Vallecito Wash has its source on the east side of the Cuyamaca Mountains, at an elevation of 2,549 feet / 777 meters, at the junction of Oriflamme Canyon and Rodriguez Canyon at 33°01′05″N 116°28′53″W / 33.01806°N 116.48139°W / 33.01806; -116.48139. It then trends southeast about 4 miles through Mason Valley to its southeast end at an elevation of 1,955 feet / 596 meters, where it continues as Vallecito Creek. The Vallecito Wash trail is suitable for scenic driving year round.

32°59′05″N 116°25′19″W / 32.98472°N 116.42194°W / 32.98472; -116.42194