Wilms’ tumor is an embryonal tumor of childhood occurring in 1 out of 1,00,000 children less than 15 years of age. An incidental case was found in the Paediatric surgery ward of Dhaka Medical College Hospital on 20th June 2012. A 3 years old girl complained of right sided painless abdominal mass for one month with occasional hematuria for 15 days. Detailed history and investigation confirmed the diagnosis as Wilms’ tumor. In developing countries most of such cases present at advanced stages. Having no scope for specific treatment, multimodal approach i.e., neoadjuvant chemotherapy followed by surgical excision has been the best choice to reduce the morbidity and mortality of these cases. Wilms’ tumor or Nephroblastoma is a cancer of kidneys that typically occurs in children. Its common name is an eponym, referring to Dr. Max Wilms, the German surgeon (1867–1918) who first described this kind of a tumor. It is the most common renal malignancy of childhood containing metanephric blastema, stromal and epithelial derivatives. It tends to be encapsulated and vascularized tumor that does not cross the midline of the abdomen. It usually metastesize to the lungs and liver. It is usually unilateral and presents with microscopic haematuria , malaise, weight loss, anaemia and sometimes with varicocele or thromboembolic disorder in the heart. A rupture of Wilms’ tumor puts the patient at risk of hemorrhage and peritoneal dissemination of the tumor. In such cases, surgical intervention by a surgeon who is experienced in the removal of such a fragile tumor is imperative.