Breast ultrasound is an adjunct to mammography and physical examination for breast masses by confirming diagnosis of cysts and providing accurate guidance for needle biopsy of vast majority of solid masses. In Sudan the incidence of cancer has been increased in the last years, this may be due to the risk factors (familial, hormonal, iatrogenic and radiation). Objectives of the study are to differentiate between cystic and solid masses, to observe criteria for differentiation between benign and malignant masses and also to increase the clinicians’ awareness regarding the important role of ultrasound guidance in interventional procedures safely.