A 19-year-old boy presented with bladder outlet obstruction and on evaluation was found to have prostatomegaly, which on biopsy was diagnostic of embryonal rhabdomyosarcoma (RMS). He had pulmonary metastasis and received chemotherapy with cyclophosphamide, doxorubicin, vincristine, actinomycin D, and radical radiotherapy. At one year, his prostatic tumour has resolved completely. Embryonal RMS of prostate occurs more commonly in infancy and childhood, so occurrence in young adults is rare, and a high index of suspicion is essential for early diagnosis and treatment.