The Baja California rattlesnake, Crotalus enyo, is a medium-sized rattlesnake restricted to the southern two-thirds of the Baja California peninsula. Very little is known about the natural history of this species. The goal of this study was to document the diet of C. enyo. I dissected the stomachs and hindguts of 113 preserved museum specimens of C. enyo and identified the ingested prey items. The diet of C. enyo consists of small rodents, lizards, and centipedes. Crotalus enyo of all sizes eat rodents and lizards, in contrast to many other rattlesnakes that eat almost exclusively lizards as juveniles and mammals as adults. However, C. enyo exhibits a modest ontogenetic shift in diet: small snakes eat lizards more often than do large snakes, and large snakes eat mammals more often than do small snakes. Adult C. enyo also eat large centipedes of the genus Scolopendra. Larger snakes tended to contain multiple prey items more often than smaller snakes, but this trend was not significant. Crotalus enyo is sexually dimorphic in size, with males being significantly larger than females. However, there is no significant gender difference in diet.