State Route 79 (SR 79) is a state highway in the U.S. state of California. The route goes from Interstate 8 in San Diego County to Interstate 10 in Riverside County.

This route is part of the California Freeway and Expressway System and is eligible for the State Scenic Highway System. However, it is not a scenic highway as defined by Caltrans. Another name of this highway is Firefighter Steven Rucker Memorial Highway: (from Route 78 in Santa Ysabel to Engineers Road in Cuyamaca). The section between those concurrent with SR 74 and Interstate 15 (in the cities of Temecula, Murrieta, Winchester, and Hemet) is posted as Winchester Road.

At Interstate 8, SR 79 is Exit 40, and intersects with the interstate about 40 miles (64 km) from its western terminus (and approximately 35 miles (56 km) east of the city of San Diego). SR 79 meets Historic U.S. 80 (now signed here as a regular road named Old Highway 80) in the town of Descanso, at a T intersection. This intersection is very clearly marked, indicating that one must turn south on Old Highway 80 and follow it to Interstate 8. SR 79 signage was added on this section of Old Highway 80 after 1996; previous to that date, the only signage was at the exit from Interstate 8 directing traffic northward on Old Highway 80. SR 79 then traverses the Cuyamaca Rancho State Park.

Then SR 79 goes through Cuyamaca and Cuyamaca Rancho State Park on its way north. This portion of the route is very serpentine, as it was constructed to follow the contours of the land by moving laterally, rather than up-and-down or via cuts. There are very sharp turns, in two cases hairpin turns posted at 15 mph (24 km/h).

It then overlaps State Route 78 between Santa Ysabel and Julian, a distance of about eight miles (13 km). At Julian, both routes join at a T intersection just south of town (which requires a turn to SR 79) and turn at an intersection in the northern portion of downtown. At Santa Ysabel, SR 79 comes to a T intersection into the east–west SR 78.

SR 79 continues west, meeting the eastern terminus of State Route 76 near Lake Henshaw and passing through Warner Springs before crossing into Riverside County. SR 79 then meets SR 371 before going east through Aguanga.

It overlaps Interstate 15 for a few miles through downtown Temecula. The ramps connecting SR 79 to I-15 are the first and third ramps (in either direction) of the three located between the I-15/I-215 junction and the Riverside/San Diego county line (these are also the only three exits on I-15 which serve Temecula). In both cases, to enter SR 79 from I-15, one must turn east (although SR 79 is signed as a north–south highway). The southern exit from I-15 is posted with the street name Temecula Parkway, which was renamed in September 2007 in the City of Temecula. SR 79 exits from I-15 in the north area of Temecula. Between I-15 and SR 74, it is consistently named Winchester Road. It then enters Murrieta before passing by the new reservoir at Diamond Valley Lake. SR 79 continues through the village of Winchester and turns east on Florida Avenue west of Hemet.

In Hemet, SR 79 overlaps State Route 74, following it westward for a few miles (which are also posted with a city street name, Florida Avenue). SR 79 goes over a range of hills (Lambs Canyon) and ends near Beaumont at Interstate 10.

Along nearly all of its length, the portion of Highway 79 south of the Interstate 15 concurrency in Temecula is a simple country road, with two lanes of traffic and no divider (the portion within the Temecula city limits is a heavily travelled city street, often four to six lanes). The portion north of Temecula (to Beaumont) varies between a two-lane country road (notably near Winchester) and a four-lane city street (in Temecula, Murrietta, Hemet, San Jacinto, and Beaumont, with a four-lane divided highway between the Ramona Expressway (at the northwest corner of San Jacinto) and the southern edge of Beaumont. (The highway section only has two access points; a signalled T intersection for a county landfill facility, and a set of highway ramps for Gilman Springs Road just north of the Ramona Expressway intersection.) The northern portion of this roadway is sometimes referred to as the Ramona Expressway.

Originally SR 79 was routed on what is now Old Town Front Street through downtown Temecula. However, it was originally routed on another road (besides Winchester Road). SR 79 was also closed during the Cedar Fire, and the towns of Cuyamaca and Julian were devastated. Fire damage is still evident from the highway.

Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, and do not necessarily reflect current mileage. The numbers reset at county lines; the start and end postmiles in each county are given in the county column.