We present a rare case of mucopolysaccharidosis (MPS) with a typical presentation of mental retardation and absence of corneal clouding. The purpose of presenting this case report is to highlight the distinctive manifestation of MPS (Hunter's disease) and to provide a concise report of Hunter's disease for medical practitioners with the hope that such information will help identify boys earlier in the course of their disease. This report is of a 7-year-old boy who presented to the children outpatient through a referral with a history of inability to grasp objects, inability to express self, and coarse skin, which started 5 years ago. On examination, he was short statured, with a big head, protruding abdomen, coarse skin, swollen wrist joints, and clubbed fingers. There was mild mental retardation. Investigations revealed mucopolysaccharides in urine ad radiographic findings were in keeping with diagnosis. Based on the clinical features and radiological findings, one can diagnose a case of MPS. However, careful and critical approach is necessary to exactly diagnose the type of MPS as enzymatic studies are not available in most centers.