The 1869 Blackburn by-election was a parliamentary by-election held in England in March 1869. It returned two members of parliament (MPs) to the House of Commons for the borough of Blackburn in Lancashire. It was a rare double-by-election, caused when the 1868 general election of the borough's two Conservative MPs was nullified. Their sons won the by-election, but the result led to fighting in the town of Blackburn and was denounced by the Liberal Party candidates as a "farce".