Born Apr. 25, 1922, in Nagano Prefecture. Japanese trade union figure.
Iwai began to work for the railroads in 1937 and became active in the workers’ movement in 1946. He was an activist in the state railroad workers’ union of Japan and was dismissed by the administration in 1953 because of his leadership of the strike movement. Iwai was general secretary of the General Council of Japanese Trade Unions from 1955 to 1970. He joined the Socialist Party of Japan in 1956. He has frequently visited the USSR as a member of trade union delegations. He was elected vice-president of the Society of Japanese-Soviet Friendship in 1972. In 1970, Iwai received the International Lenin Prize for Strengthening Peace Between Nations.