Abstract: Objective: To compare the value of ultrasound and molybdenum-target X-ray photography in the diagnosis of breast cancer.Methods: Each quadrant of breast in 78 patients suspected with breast cancer was detected by two-dimensional ultrasound.The morphology and distribution of blood flow of the internal and peripheral location of mass of patients,which was used to measure the resistance index(RI) value.The foot and 45° oblique positions of two papillas in the patients were detected using molybdenum-target X-ray photography,and if necessary,the side or local point could be detected using the mammography X-ray.The results between examination and clinicopathology were compared.Results: Among 78 patients suspected with breast cancer,the diagnostic accuracy rate of mammography X-ray(78.21%) was lower than that of ultrasound(89.74%) (P < 0.05).The diagnostic accuracy rate of the necrosis and extent of breast cancer of ultrasound were significantly higher than those of mammography X-ray(P < 0.01),the difference of the diagnostic accuracy rate in axillary lymph node metastasis between mammography X-ray and ultrasound was not statistically significant(P > 0.05).The diagnostic accuracy rate of calcification of ultrasound was significantly lower than that of mammography X-ray(P < 0.01).Conclusions: Ultrasound and mammography X-ray have its certain advantage in the diagnosing of breast cancer.The diagnostic methods can be selected according to actual situation,which can improve the clinical diagnosis accuracy.