The Young Communist League of Canada (YCL-LJC) is a Canadian Marxist–Leninist youth organization founded in 1922. The organization is ideologically aligned with, but organizationally independent from, the Communist Party of Canada. The organization's members played a leading role in the On-to-Ottawa Trek and made up a significant portion of the Mackenzie–Papineau Battalion, which fought on the Republican side in the Spanish Civil War.