Background: The combined use of renal biochemistry and ultrasonographic imaging may improve the correct management of renal disease. Although renal disease is frequently observed in nonhuman primates, renal function markers have not yet been studied in Squirrel monkeys (Saimiri collinsi). Objectives: The aim of this study was to establish normal renal biochemistry variables and ultrasonographic features in Squirrel monkeys. Material and Methods: Renal biochemistry variables and ultrasonographic images were documented in 29 healthy Squirrel monkeys (15 males and 14 females). Urea, serum creatinine (SCr), and uric acid (UA) concentrations were measured by kinetic assay. Cystatin C (CysC) was analyzed by immunonephelometry. A multiple frequency linear array probe (5–12 MHz) was used for ultrasonographic imaging. The studied indicators of renal function were related to sex, age, and body mass. Results: Serum creatinine was influenced by sex and body mass. Serum concentration of urea, UA, and CysC were not influenced by sex, age, and body mass. Ultrasonographic images provided accurate and comprehensive data for making clinical decisions for Squirrel monkeys. The total renal volume was only influenced by the body mass nested in sex and was positively correlated to body mass. Right renal volume was bigger than the left one. Conclusion: Normative standards for the renal evaluation, including biochemistry and ultrasonography, in the Squirrel monkey have been established correlated to age, sex, and body mass.