56 cases of Ultrasonography in patient with proven pelvic mass were reviewed. Ultrasonography is a very usefulnoninvasive diagnostic modality in the patient with clinically suspelcted pelvic masses giving accurate assessmentof the size, location, internal structure and origin as well as its existence. A specific diagnosis as possible inselected patients with ovarian cystadenoma, dermoids, uterine myoma, and H-mole. Nonspecific pattern was common inpelvic abscess and ectopic pregnancy. Diagnostic errors were primarily due to small lesions(2cm or less indiameter) or misinterpretation of the lesion.