Jacob Penner (August 12, 1880 – August 28, 1965) was a popular international socialist politician in Canada. A founder of the Social Democratic Party of Canada and the Communist Party of Canada, Penner was elected to the Winnipeg city council in 1933. He would remain at that post until 1960, becoming the longest serving elected Communist city council member in North America. During World War II, Penner would become the first Canadian Communist interned for political security reasons. He would be incarcerated from June 1940 until being granted his release in July 1942.