After the war, Valenciennes turned professional again and were back in the second division. The club spent a decade in Division 2 before earning promotion the top-flight ahead of the 1956–57 season. Under manager Charles Demeillez, in 1951, Valenciennes reached the final of the Coupe de France. In the final, the club faced Strasbourg and were humbled 3–0 at the Stade Olympique Yves-du-Manoir in the Colombes. In the club's return to Division 1, Valenciennes finished in the latter part of the table for three consecutive seasons. In 1959, Valenciennes reached the final of the Coupe Drago, but were defeated 3–2 in extra time by Lens at the Parc des Princes. In the 1959–60 season, Valenciennes achieved its best finish in Division 1 after finishing 8th in the table. However, manager Robert Domergue was unable to keep the consistency as Valenciennes finished 19th in the following season. Valenciennes, now being led by youngsters Bolec Kocik and Serge Masnaghetti, achieved promotion back to Division 1 after one season and spent the next nine years playing in Division 1. During the stint, Domergue led to club to its highest finish ever in the first division when the club finished 3rd in back-to-back seasons in 1965 and 1966. After the 1966 season, Domergue departed the club and he was replaced by Gaby Robert. Neither Robert or his successor Louis Provelli could match the consistency of Domergue and he returned to the club in 1970. In the club's first season back, Domergue led the club to relegation in 1971, got the club promoted back to the first division in 1972, and coached the club to relegation again in 1973. He departed after the season and was replaced by Jean-Pierre Destrumelle.