Isolated renal glycosuria is a rare genetic disease caused by mutations in SLC5A2 gene. The mutation leads to a defect in glucose transporter, sodium-glucose co-transporter 2 (SGLT2), which is involved in the reabsorption of glucose from proximal tubules. Defect in this transporter leads to loss of glucose in urine. This rare disease has not been reported from Nepal previously, and here we report the first case. A 38-year-old female with complaint of tiredness and fatigue visited our medical centre. On clinical examinations, no other signs and symptoms were reported. The patient had no history of any other disease and the patient was not taking any supplements or medications. On repeated laboratory investigations, there were no signs of abnormal glucose metabolism and proximal tubular dysfunction. No evidence of hepatic, renal, and blood disorders, infection, haematuria, and proteinuria was present. Based on clinical and laboratory investigations, the patient was diagnosed as having isolated renal glycosuria. We report the first case of isolated renal glycosuria in Nepal. Because the disease is often asymptomatic, physicians and health professionals need to be aware of this condition which may occur in their community.