The Slave Trade Felony Act 1811 (51 Geo. 3. c. 23) was an act of the Parliament of the United Kingdom that made engagement in the slave trade a felony. The earlier Slave Trade Act 1807 (47 Geo. 3 Sess. 1. c. 36) merely imposed fines that were insufficient to deter entrepreneurs from engaging in such a profitable business. The contexts in which it could be applied and how these sat within international criminal law gave rise to controversy. Henry Brougham was the principal proponent of the act.

The first case brought under the act was that of Samuel Samo, who was tried by Chief Justice Robert Thorpe at the Vice-Admiralty Court in Freetown, Sierra Leone. The case was heard from 8 April to 11 April 1812.

The whole act was repealed by section 1 of, and the schedule to, the Statute Law Revision Act 1861 (24 & 25 Vict. c. 101), which came into force on 6 August 1861.