Although he started as a road cyclist, Luigi Roncaglia had his most success on the track, winning team pursuit medals at both the 1964 and 1968 Olympics, with silver in 1964 and bronze in 1968. Roncaglia won gold in team pursuit at the 1963 Mediterranean Games. He was Italian Champion in 1964 in both individual and team pursuit, while at the World Championships he helped Italy win team pursuit gold in 1966 and 1968, with a silver medal in 1967.
Roncaglia also rode six-day races, winning at Milano in 1966, and placing second at that race in 1967. He turned professional in 1968, winning a Melbourne six-day race in 1969 after placing second at the end of 1968. Roncaglia was awarded the Gold Medal of the Italian Olympic Committee for his cycling achievements.