Mission San Pedro Mártir was established by the Dominican missionary José Loriente on 27 April 1794, in the Sierra San Pedro mountain range in northern Baja California, Mexico.
Located at an elevation above 1,500 meters above sea level and far inland, Mission San Pedro Mártir appears to represent an initiative by the Dominicans to extend control over the Kiliwa Indians who had lived outside the scope of the earlier coastal missions. The first site of the mission was Casilepe; later in the same year it was relocated to Ajantequedo, about 13 kilometers to the northeast. The date for the closing of the mission is somewhat uncertain, being reported as both 1806 and 1824. The mission's neophytes were relocated to Mission Santo Domingo.
Archaeological explorations have located possible traces of the first mission site. Foundations and walls survive at the second mission site.