The 1940 Cork Junior Football Championship was the 42nd staging of the Cork Junior Football Championship since its establishment by the Cork County Board in 1895.
The final was played on 10 November 1940 at the Athletic Grounds in Cork, between Ballincollig and Youghal, in what was their first ever meeting in the final. Ballincollig won the match by 1âÂÂ06 to 1âÂÂ03 to claim their second championship title overall and a first championship title in seven years.