Introduction: Renal angiomyolipoma (AML) has been increasingly diagnosed incidentally in the cross-sectional radiological study. Case presentation: We present a renal AML in a 16-year-old girl who presented with increasing abdominal distention and irregular menstruation for the last 2 months. Contrast-enhanced computed tomography (CECT) abdomen and chest revealed abdominopelvic hypodense predominantly cystic attenuation mass measuring 40.6 × 24.7 cm with internal septation with significant wall enhancement. A whole-body positron emission tomography–computed tomography (PET-CT) scan revealed a faintly fluorodeoxyglucose (FDG) avid well-circumscribed lesion measuring 14.3 × 24.7 × 40.7 cm with high-dose (HD) unit-20. Ultrasonography (USG)-guided fine needle aspiration cytology (FNAC) revealed low-grade/benign spindle cell neoplasm. The resected surgical specimen was 45 × 26 × 30 cm and weighed 12.5 kg. Histopathology and immunohistochemistry (IHC) reports favored AML. Conclusion: The giant AML, in our case, is heaviest by weight and largest by dimension in both sporadic and syndromic renal AML, as reported in the literature.