Dissatisfied with the direction of the Quebec Liberal Party, he helped found the Action libérale nationale party on June 6, 1934. He soon formed an alliance with Maurice Duplessis's Quebec Conservative Party to contest the 1935 provincial election. Gouin withdrew his support from Duplessis on June 18, 1936, but most members of the ALN caucus sided with Duplessis and joined with his Conservative caucus to formally merge into the Union Nationale party, which not long afterwards won the 1936 election.
He re-formed the Action libérale nationale and became its leader on July 24, 1938. However, the ALN did poorly in the 1939 election, winning only 4.5% of the popular vote and no seats, and soon disbanded. He helped found the Bloc populaire canadien in 1942, but left it in early 1944 when André Laurendeau was chosen to lead the Quebec wing of the party.