The Bermondsey by-election, 1909 was a by-election held on 28 October 1909 for the British House of Commons constituency of Bermondsey in South East London. It returned one Member of Parliament (MP) to the House of Commons of the United Kingdom, elected by the first past the post voting system. The presiding officer and the ballots were damaged by two suffragettes who tried to disrupt the men's election.