Objective To construct a breast cancer opportunistic screening system based on data mining and verify its application effect.Methods The screening management system was constructed based on data mining.The patients who underwent breast cancer opportunistic screening from January 2021 to May 2024 were selected and divided into a control group and an observation group according to the system before and after application, with 2 373 cases in each group.The observation group used the system for screening management, while the control group adopted the conventional screening management methods.The time of definite diagnosis and hospitalization, and the satisfaction with opportunistic screening for breast cancer were compared between the two groups.Results The time for clear diagnosis and hospitalization in the observation group was significantly shorter than those in the control group, and its satisfaction score for breast cancer opportunistic screening was significantly higher than that in the control group （all P＜0.05）.Conclusion The application of breast cancer opportunistic screening system based on data mining for screening management can shorten the time from screening to first admission for treatment, promote early diagnosis and treatment of patients, and improve patients′ satisfaction.