Peromyscus guardia Townsend, 1912 is a small, gray-brown cricetid commonly called the La Guarda deermouse. It is a Mexican endemic rodent from Angel de la Guarda Island and 2 islets off the northern tip of Angel de la Guarda in the Gulf of California. Populations of P. guardia were common up until the mid-1960s but have since declined. This species is currently listed as “Critically Endangered” by the International Union for Conservation of Nature and Natural Resources.