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Risk of rattlesnake predation was assessed in laboratory experiments for two bipedal and two quadrupedal species of desert rodents. Rodents were left overnight with Great Basin rattlesnakes (Crotalus viridis lutosus) in experimental arenas that had either 37% sagebrush-canopy cover or no cover. Predation rates did not differ significantly between arena types for any one rodent species or for all four species grouped. The lack of a shrub-cover effect on risk suggests that rattlesnake predation cannot account for microhabitat associations found in desert rodents. Risk did not differ between bipedal and quadrupedal species, but differed significantly among individual species. Dipodomys merriami and Peromyscus maniculatus seldom were caught by rattlesnakes, but Microdipodops megacephalus and Perognathus parvus often were caught. Such species differences in risk may affect foraging behavior and distribution patterns of some species of desert rodents.