We sought to determine whether sex had a significant effect on the hematologic and serum chemistry analytes in adult sand rats (Psammomys obestls) maintained under normal laboratory conditions. According to the few data available for this species, we hypothesized that levels of hematologic and serum chemistry analytes would not differ significantly between clinically normal male and female sand rats. Data analysis revealed several significant differences in hematologic parameters between male and female sand rats but none for serum biochemistry analytes. The following hematologic parameters were greater in male than in female sand rats: RBC count, hemoglobin, hematocrit, red cell hemoglobin content, and percentage monocytes. Red cell distribution width, hemoglobin distribution width, mean platelet volume, and percentage lymphocytes were greater in female than in male sand rats. The sex of adult sand rats is a source of variation that must be considered in terms of clinical and research data. The data presented here likely will prove useful in the veterinary medical management of sand rat colonies and provide baseline hematologic and serum chemistry analyte information for researchers wishing to use this species.Approved for public release; distribution is unlimited.