We present a case of a 28-year-old male who presented with acute abdomen and was later diagnosed to be having ruptured intra-abdominal seminoma with hemoperitoneum, where the pre-operative diagnosis was not made. Laprotomy and complete excision were carried out. Rupture of intra-abdominal testicular seminoma is a rare cause of acute abdomen and hemoperitoneum. The pre-operative diagnosis is often difficult because history of cryptorchidism is not provided and imaging findings may be non-specific. In a male patient with acute abdomen and without previous history of orchidectomy, a testicular aetiology of acute abdomen should be kept as the differential diagnosis.