Santiago Lazcano (8 March 1947 in Errezil – 3 February 1985 in San Sebastián) was a Spanish cyclist. He debuted as a professional in 1969 and rode both the Vuelta a España and Tour de France that year. He finished 10th overall in the 1972 Giro d'Italia and his best season was 1973 as he won the Spanish mountain championship, the Villafranca Grand Prix and took 5th overall in the 1973 Giro d'Italia. In 1974 he won stage 17, a high mountain stage in the Giro d'Italia and he finished 10th overall in the 1975 Vuelta a España. He retired as a pro cyclist in 1976 after an accident with a car at a race in The Netherlands. Following his retirement he occasionally commentated on the radio and on a regional TV show called 6 Hours of Euskadi. He died in a motorcycle accident close to his home in Azpeitia.