One in every nine women is expected to develop breast cancer in her life. Current mainstream screening technology is the mammography. Mammography suffers from a range of problems including low signal level, poor contrast, and radiation dose. It leads to severe over-diagnostic problems. In contrast, our breast cancer screening system with color X-ray phase tomosynthesis can achieve a dramatically enhanced contrast (about 1000 X larger than attenuation at clinic energies), as well as targeted differentiation between normal breast tissue and hardening carcinoma. The outcome is greatly improved accuracy and specificity for breast cancer screening.