Parley Parker Pratt Sr. (April 12, 1807 – May 13, 1857) was an early leader of The Church of Jesus Christ whose writings became a significant early nineteenth-century exposition of the Latter Day Saint faith. Named in 1835 as one of the first members of the Quorum of The Twelve Aposltes, Pratt was part of the Quorum's successful mission to Great Britain from 1839 to 1841.