The Sierra San Pedro Martir is a mountain chain that runs north-south along the northern part of Baja California in northwest Mexico. The highest point is Cerro de la Encantada, 3096 m.

The mountains are connected to the Laguna Mountains and San Jacinto Mountains in southwest California, and have a very similar flora to these ranges, distinct from the flora of the rest of Mexico. Typical species include White Fir, Sugar Pine and Jeffrey Pine.