Thomas Walsh (3 October 1777 –18 February 1849) was an English Catholic prelate who served as Vicar Apostolic of the London District from 1848 until his death.
In 1793, the French Revolution and the United Kingdom's declaration of war on France ended the Saint Omer college.
In 1795, Gregory Stapleton, President of the college, obtained from the directory an order for the release of the sixty-four students.
In 1848, he was named, despite his reluctance, Vicar Apostolic of the London District, with the intention of him being the first Archbishop of Westminster when the hierarchy was to be restored in 1850 but he was too old and infirm at 71 to take any active part in its affairs, and so left its administration in the hands of his coadjutor, Bishop Nicholas Wiseman.
A large Gothic-revival memorial to him with a recumbent effigy, designed by Pugin and carved by George Myers, was erected in the North aisle of the Cathedral in 1851, after being exhibited in the Mediaeval Court of the Great Exhibition in The Crystal Palace, Hyde Park, London.