Objective To investigate the average glandular dose of digital mammography in Zigong, China, and to explore the methods of reducing average glandular dose. Methods A total of 260 patients who underwent digital mammography at six hospitals located in Zigong during the year 2022 were included in this study. Their personal information, photography position, breast compression thickness, exposure parameters, and average glandular dose were collected. Analysis of variance and correlation analysis were performed for data analysis. Results Among the 260 patients who underwent digital mammography, the average breast compression thickness was 46.3 mm and the average glandular dose was 1.70 mGy. There was a significant difference in average glandular dose between patients with different breast compression thickness(P <0.05), and average glandular dose was positively correlated with breast compression thickness. There were no significant differences in average glandular dose between patients with different photography positions and patients with different ages (P>0.05). Conclusion The average glandular dose of patients undergoing digital mammography is at an acceptable level in Zigong. The average glandular dose is impacted by the breast compression thickness, target/filter, and exposure parameters. These factors should be optimized to reduce glandular dose during digital mammography.