IntroductionAno-rectal abscesses are common. They however usually do not present with abdominal symptoms. CT although useful is not routinely carried out. Finding of Pneumo-retro-peritoneum with ischio-rectal abscess is rare.Case presentationWe present the case of a diabetic gentleman who presented with abdominal pain and distension and was found to have ischio-rectal abscess on perianal examination. Although initially suspected to have acute abdomen due to perforated viscus, CT scan revealed pneumo-retro-peritoneum which appeared to arise due to the abscess. Patient underwent incision and drainage of the abscess followed by serial debridement. He made a complete recovery.ConclusionAbdominal symptoms are rare in ischio-rectal abscess, but they must be kept in mind. Proper diagnosis may avoid a negative laparotomy.