Martin Boos (25 December 1762 - 29 August 1825) was a German Roman Catholic theologian.

He was born at Huttenried in Bavaria. Orphaned at the age of four, he was reared by an uncle at Augsburg, who finally sent him to the university of Dillingen . There he laid the foundation of the modest piety by which his whole life was distinguished. After serving as priest in several Bavarian towns, he made his way in 1799 to Linz in Austria, where he was welcomed by Bishop Gall , and set to work first at Leonding and then at Waldneukirchen , becoming in 1806 pastor at Gallneukirchen . His pietistic movement won considerable way among the Catholic laity, and even attracted some fifty or sixty priests.

The death of Gall and other powerful friends, however, exposed him to bitter enmity and persecution from about 1812, and he had to answer endless accusations in the consistorial courts. His enemies followed him when he returned to Bavaria, but in 1817 the Prussian government appointed him to a professorship at Düsseldorf, and in 1819 gave him the pastorate at Sayn near Neuwied. He died in 1825.

See Life by Johannes Gossner (1831).