Objective:The incidence of breast cancer in Chinese women continues to rise. The large breast cancer cohort studies in China are relatively scarce. There are many bottlenecks in the construction of large clinical cohort for breast cancer diagnosis, treatment, and prognoses, such as inconsistent standards, high rates of lost follow-up, repeated construction, and inability to share. To better solving the difficulties and problems faced by large-scale clinical cohort research in China, this project will cooperate with several tertiary A hospitals to establish a breast cancer cohort in Chinese women. It also provides a data platform and technical support for breast cancer multi-center clinical cohort research.Methods:Based on the evidence-based medicine and expert opinion and consensus, we established a breast cancer cohort standardized indicator set-recording baseline information, diagnosis and treatment-related information of the enrolled patients, and collecting biological specimens. According to the technical specification of long-term follow-up for the endpoint, data management, and data security and in the large population-based cohort study, a standardized follow-up system for the diagnosis, treatment, and prognosis of breast cancer prospective cohorts is formed.Results:Based on standardized data sets and the computer discipline’s advantage from the University of Science and Technology Beijing, we integrate the new information technology methods, including dynamic information collection terminals and social networks. Thus, the quality of control programs on compliance and intelligence data was improved, and a Chinese women breast cancer cohort database was developed. By February 2020, 12 147 patients were included in the clinical cohort database. Biological specimens’resources in cohort construction were collected and cooperated with Shandong University to research the multi-center quality control system and shared evaluation system of biobanks. Building an open and shared biobank network and forming a full chain of breast cancer research platform.Conclusion:With the implementation of the "13 th Five-Year Plan" precision medicine research, this study provides a research foundation for precision diagnosis and treatment of breast cancer and provides data support for the country to formulate relevant medical policies.