Having starting his youth career in Union Saint-Gilloise, Demol played also for Union's first squad from 1914 on. In his first professional year, he would already lift the Belgian Cup. With the same team (in the meantime named Union Royale Saint-Gilloise), he also won the Belgian Championship for clubs nine years later. In 1927, he changed Union after 176 games and 19 goals[4] for Third Division team RC Tienen as coach, with which he celebrated promotion to Second Division in 1931.
Frans Demol became a football manager in 1927 for RC Tienen and in 1944 for Belgium. Under his supervision the national side won twice, drew twice and suffered four losses.[1] In 1946, Englishman Bill Gormlie became his successor as coach of Belgium. Just as for his player career, Demol's career as football manager ended up in Tienen; he would lead this team during only one year.
