Thomas Stephens (21 April 1821 – 4 January 1875) was a Welsh apothecary, historian and critic. He was born at Pont Nedd Fechan, Glamorganshire, the son of a shoemaker. His works include The Literature of the Kymry (1849), The History of Trial by Jury in Wales, and an essay in which he demolished the claim of the Welsh under Madoc to the discovery of America. He also wrote on the life and works of the bard Aneurin, and produced an English translation of Y Gododdin. The critical methods that he adopted in his works often made him unpopular with the less discriminating enthusiasts for the glory of Wales, but he earned the respect of serious scholars.
Thomas Stephens' manuscripts are now part of the National Library of Wales General Manuscript Collection.