Captain George Mainwaring (/ˈmænərɪŋ/ MAN-ər-ing) is the bank manager and Home Guard platoon commander portrayed by Arthur Lowe on the BBC television sitcom Dad's Army, set in the fictional seaside town of Walmington-on-Sea during the Second World War. He has become widely accepted and regarded as a classic British comic character owing to the popularity of both Dad's Army and Lowe's portrayal of him.

The role of Captain Mainwaring was originally intended for Jon Pertwee, later famous as the Third Doctor, but he turned it down so that he could do a play on Broadway.