Objective To discuss MRI scan in the diagnosis and clinic-pathology of ovarian cystoid-material lesion.Methods We retrospectively analyzed 41 patients with clinic pathologically-proved in 2005~2007,and analyzed US,MR scan and Gd-DTPA in the diagnosis of ovarian cystoid-material lesion.Results The clinical date of the 87 patients were completed.After operation,41 of them were confirmed by pathology to be cystiform or parenchymal process,with age 16~76,average 56,of which,21 cases,were tumour-like lesions occupying 51.2%,18 cases were timorous lesions,occupying 30.2%,13 cases weer ovarian cystadenoma,occupying 30.2%,and 2case ueve other disense,occupying 4.65%.Conclusion The benign often present as ovarian cystoid-material lesion.MRI scan can show the inner structure of ovary lesion.