Breast microcalcifications are one of the important indicators for early breast cancer detection. Currently, X-ray mammography and ultrasound imaging are routine diagnostic tools in clinics for breast cancer; however, X-ray mammography is with ionizing radiation and thus there is inevitably carcinogenic risk. Ultrasound (US) imaging also suffers speckle noises, resulting in low contrast between breast tissues and micro-calcifications. In this paper, we report on the first demonstration of photoacoustic (PA) imaging for micro-calcification detection. Compared with X-ray mammography and US imaging, PA imaging owns the features of non-ionizing radiation, speckle free, high optical absorption contrast given an optimal wavelength, and good ultrasonic resolution as well. A 10-MHz confocal PA imaging system was employed to verify our idea in this study. A chicken breast tissue phantom with granulated calcium hydroxyapatite (HA) embedded was imaged. The HA particles were served as calcification particles because HA is the major chemical composition of the breast calcification associated with malignant breast cancers. Optimal excitation wavelengths at the near infrared window for PA imaging of HAs were also analyzed. The imaging results showed that the distribution of ~500 μm HAs could be clearly revealed in the PA image (right panel in the figure) while it was hardly identified in the US B-mode image (left panel in the figure) because of speckle noise. In summary, from out results, PA imaging show its promise as a new imaging modality for breast micro-calcification detection. In addition, co-registration of the PA and US images can further render the locations of micro-calcifications within anatomical landmarks of the breast tissue, which is clinically useful for biopsy and diagnosis of breast cancer staging.