PURPOSE: To determine role of the US in identifying and localizing breast microcalcifications with and without mass, and to evaluate reliability of US guided core biopsy. To evaluate the role of color and power Doppler with spectral vaweform analysis and measurement resistance index in breast lesions with and withouh microcalcifications. ----- MATERIAL AND METHODS: 140 women were examined with US including color, power and spectral vaweform analysis. 70 women had a MMG visible microcalcifications clusters with associated mass and 70 women had microcalcifications only. All underwent core biopsy under US guidance. Clinical, morphological and pathologic findings were retrospectively rewieved. ----- RESULTS: 91% women with microcalcifications and soft tissue mass had positive US examination. 74% women with only microcalcifications cluster had positive US examination. All lesions underwent core biopsy under US guidance. 46% women with microcalcifications and 72% women with microcalcifications and mass have positive color and power Doppler examination. With Color and power Doppler, and with spectral vaweform analysis (SFA) we measured vascular characteristic of lesion. Measurement of resistence index is also done, and with SFA we distinguish vascularizations from artifacts. ----- CONCLUSIONS: US is an accurate method to identify breast lesions with microcalcifications, and also an effective method for tissue-sampling of breast microcalcifications. US guided biopsy can be used as alternative method to stereotactic MMG biopsy. US Color and power Doppler with spectral vaweform analisis (SFA) are sensitive indicator of vascularization inside lesions, but for now have not a significant role in diagnosis of lesions with microcalcification.