Ask a Policeman is a 1939 British comedy film directed by Marcel Varnel and starring Will Hay, Moore Marriott and Graham Moffatt.

William Thomson Hay was an English comedian who wrote and acted in a schoolmaster sketch that later transferred to the screen, where he also played other authority figures with comic failings. His film Oh, Mr. Porter! (1937), made by Gainsborough Pictures, is often cited as the supreme British-produced film-comedy, and in 1938 he was the third highest-grossing star in the UK. Many comedians have acknowledged him as a major influence. Hay was also a keen amateur astronomer.