Objective To study the clinical CT manifestations of infective ovarian cysts so as to improve diagnostic ability.Methods All the cases were evaluated on plane scan and enhancement scan.Their manifestations on CT were analysed.Results The cysts lying in the left ovary account for 14 cases, in the right ovary 4 cases. The size of cysts varied from 11 cm?10 cm?11 cm to 4 cm?3 cm?4 cm. The cyst walls thickened to some extent. 15 cases thickened “gradually”. 3 cases thickened “comparatively evenly”. The thickness of the cyst walls was over 1 cm, the thickest being 2 cm. The length of the thickened wall was more than one half circumference of the cyst, with smooth inner side.The cyst wall showed the density of soft tissues and it was mildly intensified after being enhanced.Conclusion The clinical CT manifestations of infective ovarian cysts have certain characteristics.