Both kidney and adrenal gland disease have been identified in callimicos (Callimico goeldii). Ultrasonography (US) and computed tomography (CT) are routinely utilized in veterinary patients with suspected renal or adrenal disease to determine size, shape, and echogenicity of these organs. No previous US and CT kidney and adrenal gland measurements have been published for callimicos. In this study, 14 callimicos were anesthetized using isoflurane via facemask to evaluate kidney and adrenal gland size using US for both organs and CT for kidneys. Animals were considered clinically healthy based on history, physical examination, hematology, serum chemistry, urinalysis, and abdominal US. Ultrasound organ measurements for length (L), width (W), and height (H) in centimeters (mean/median, 95% confidence interval) in clinically healthy animals were right kidney (L = 1.90, 1.76–2.01; W = 1.05, 0.97–1.13; H = 1.59, 1.48–1.69), left kidney (L = 1.84, 1.72–1.95; W = 1.16, 1.04–1.28; H = 1.54, 1.43–1.65), right adrenal gland (L = 0.38, 0.33–0.57; H = 0.19, 0.15–0.31) and left adrenal gland (L = 0.36, 0.32–0.39; H = 0.18, 0.17–0.20). All kidney measurements were positively correlated with animal weight (P < 0.05) but had no significant correlation to age. Measurements did not have any significant relationship to evaluated blood and urine parameters. Results from this study establish baseline measurements for callimico kidneys and adrenal glands to help clinicians use these imaging modalities for evaluation of these organs in this endangered species.