The 1942 Maldon by-election was a parliamentary by-election held on 25 June 1942 for the British House of Commons constituency of Maldon in Essex. It was one a series of by-elections in World War II won by radical independent candidates.

Maldon is a constituency in Essex represented in the House of Commons of the UK Parliament since its recreation in 2010 by Sir John Whittingdale, a Conservative.