Harry Douglass, Baron Douglass of Cleveland (1 January 1902 – 5 April 1978) was a British trade unionist. Born in Middlesbrough, England, Douglass entered work at the age of 13, becoming a steel melter. He immediately joined the Iron and Steel Trades Confederation, and became a member of its executive council in 1933. Two years later, he was appointed as a full-time organiser for the union, then rose to become Assistant General Secretary in 1945 and finally General Secretary in 1953, serving until 1967. He was also President of the International Metal Workers' Federation.