Margarito Bautista Valencia (1878-1961) was a Mexican Mormon fundamentalist.

Margarito Bautista was born on June 10, 1878 to a bilingual (Nahua and Spanish) peasant family in the San Miguel de Atlautla, Mexico State. In the summer of 1901, Margarito Bautista was visited by two Latter-day Saint missionaries as he lay in his bed ready to die. They gave him a blessing and shortly his health improved. After a few weeks, he was baptized into the Church of Jesus Christ of Latter Day Saints. In 1913, Bautista moved north to Arizona and then Utah to flee the Mexican Revolutionary War. From 1922-24, Bautista served as a Latter-day Saint missionary in central Mexico, and then returned to live in Mexico in 1935. In 1936, Bautista was a candidate for the Mexican Mission Presidency under the Third Convention (he later withdrew his name). He fell away from the Church of Jesus Christ of Latter-day Saints, and eventually the Third Convention, and organized his own congregation, The Fullness of the Kingdom of God. As the leader, he wrote many pamphlets and proselytized to gain members. The colony went through episodes of alignment with several other Mormon fundamentalist groups, but in the end kept to themselves and built a temple. The group still exists as of 2014, with over a thousand members. Margarito died at the age of 83 in 1961.