Since capturing its first CIF-SS title in Boys Cross Country in 1977, the Valencia High School athletic program continues to make a name for itself throughout Orange County. While academics remains a constant emphasis at Valencia High School, the school is proud of its athletic program's success. To date the school has won 274 league championships, 17 CIF-SS championships, been CIF-SS Runner-up 29 times, captured 36 Individual CIF-SS championships 6 CIF Masters Championships 1 CIF-State Runner-up and 6 Individual CIF-State championships.

Valencia High School opened its doors in the Fall of 1935, and its boys' athletic teams became a member of the CIF-SS that same year, fielding teams in football, basketball, baseball and track. Today, the boys' compete in 13 sports.

From 1935 to 1976 girls' athletics competed in the Girls Athletic Association or "G.A.A" , they fielded teams in basketball, field hockey, volleyball, badminton, and tennis. In 1977 girls' athletics became a member of the CIF-SS and today they compete in 11 sports.

Although both the boys and girls teams had some success from 1935-1979, it has been from 1980 till today that the school and its athletic programs have made their mark in Orange County. Competing first in the Orange League and now in the Empire League, the boys and girls programs have combined to win 246 League Championship, 16 CIF Championships, 28 CIF Runner-Up titles, 35 Individual CIF Championships 6 CIF Masters Championships 1 CIF-State Runner-Up and 6 Individual CIF-State Championships.