To discern characteristic computed tomography (CT) findings of tubo-ovarian abscess (TOA), we retrospectively reviewed the CT and pathological findings on 22 cases of TOA in 13 patients. The main pelvic lesion on CT mostly corresponded to ovarian abscess, and satellite lesions corresponded to pyosalpinx on pathological examination. We conclude that the characteristics of CT findings that may be suggestive of TOA are peripherally enhancing low-density pelvic mass, anterior displacement of the round ligament, and, especially, the presence of satellite lesions adjacent to main masses.