Wheatley was born in Ireland, but in 1876 the family moved to Lanarkshire in Scotland. Initially, he worked as a miner, as his father had done, but he later ran his own successful printing business which specialised in publishing leftist political works, many of which Wheatley wrote himself.
A deeply religious man, (he was a practicing Catholic) he was influenced by early Christian-socialist thinkers, and in 1907 he joined the Independent Labour Party (ILP).
He was involved with in campaigning againts Britain's involvement in the First World War, campaigning against conscription, and assisting the organisation of rent strikes in Glasgow.
He sat as a councillor on Glasgow's city council, becoming one of the best known in the city, before being elected to the House of Commons in the 1922 General Election.
The Labour leader, Ramsay MacDonald disapproved of Wheatley's debating methods which led to his suspension from the Commons on various occassions. He worked closely with his ILP colleagues in the Parliamentary Labour Party, especially, James Maxton. He was known to be the intellectual behind the ILP activities. Along with many of the other ILP MPs, especially those from Clydeside Wheatley found himself drifting from the Labour leadership under MacDonald.
However, Wheatley remained a widely respected poltical figure and when MacDonald became Prime Minister in January 1924, he appointed him as his Minister of Health. Wheatley's is best remembered for his Housing Act, which he introduced in this period, which saw a massive expansion in affordable municipal housing for the working-classes
Wheatley criticised MacDonald's moving Labour to the right and consequently found himself unappointed to the Labour Government formed after the 1929 General Election. He refused to support many of the measures proposed by MacDonald's government and along with Maxton (by now Wheatley's leader in the ILP) became one of the Labour-left's leading critics.
John Wheatley died on May 12, 1930. John Wheatley College in Glasgow is named after him.