Stephen Joseph Perry SJ FRS (26 August 1833 – 27 December 1889) was an English Jesuit and astronomer, known as a participant in scientific expeditions.

In consequence of his marked bent for mathematics, he was sent to attend the lectures of Augustus De Morgan, in London, and those of Bertrand, Liouville, Delaunay, Cauchy, and Serret, in Paris.

In 1870 he was in charge of a government expedition to observe a solar eclipse at Cadiz; at Carriacou (West Indies) in 1886; in Moscow in 1887; and at the Îles du Salut in 1889, on which journey he died.

He took a series of observations to determine the absolute longitude of the place, and others for the magnetic elements, at Kerguelen, the Cape, Bombay, Aden, Port Said, Malta, Palermo, Rome, Naples, Florence, and Moncalieri.

At Stonyhurst College, while he greatly developed the meteorological work of the observatory, and in the province of astronomy made frequent observations of Jupiter's satellites, stellar occultations, comets, and meteors, it was in the department of solar physics that he specially laboured, paying particular attention to sun spots and faculae.