Background: Breast cancer is the most common cancer found in women, and screening is the best way to make an early diagnosis. The aim of this study was to determine the rate of screening mammography and related variables in the mammography center of Mousavi Hospital, located in Zanjan, Iran. Methods: This was a prospective descriptive study. Study sample size was 526 women who were selected by a convenience sampling method. Data collection instrument was a multisection questionnaire and this was completed by a trained radiology technologist through interviews. In cases referred to ultrasonography or histopathological evaluation, follow-up of the women was conducted to obtain their results. Results: Results showed that the rate of screening mammography was 27.4%. Educated women and women, who had a family history of breast cancer, were more likely to have a screening mammography. Among the referrals, 71% were between the age of 30-50 years and the most common complaint in the diagnostic mammography patients was breast pain. The findings of mammography in 33% of patients were normal, 2.3% were malignant and the rest of the cases were as follows: dense breast, axillary lymph node, benign mass, fibrocystic breast and calcification. For the women who had a further evaluation; 26% were referred to ultrasonography, and 1.4% were referred for a breast biopsy. The findings of ultrasonography and pathology confirmed malignancy in 4 women. Conclusion: According to the study's results, there is a need to provide information and mass education about screening mammography, breast cancer risk factors and symptoms in Zanjan.