Santa Monica Mountains National Recreation Area is the nation’s largest urban park and has lacked knowledge about its small mammal communities. Information on small mammal natural history, species richness, and abundance is needed by managers to determine where small mammals occur and where they are the most diverse. We used live-traps to characterize the small mammal community at 30 sites in the two most abundant habitat types: chaparral and coastal sage scrub. The sites were co-located with existing long-term vegetation survey sites, and vegetation structure covariates were considered to explain the variation in small mammal distribution and diversity. Capture success was high, and we captured 11 native species, including 2 heteromyids, 5 Peromyscus species, 2 woodrats, harvest mice and voles, the full predicted small mammal fauna. We found healthy small mammal communities in both habitat types and across the park. These baseline data will be used to measure the success of native plant restoration projects and verify that restored areas function as habitat for small mammals. Small mammals are a good proxy for general wildlife response to restoration, because rodents interact with native plants through seed predation, herbivory, and soil disturbance, and are a critical food source for predators.