BackgroundBreast cancer is a major global public health concern and a major cause of cancer-related mortality. In 2020, 8.3% of the total breast cancer deaths worldwide were reported from China, which highlighted the need to understand the epidemiological trends of breast cancer within the country. Therefore, this study aimed to analyse the trends in the breast cancer burden in China from 1990 to 2021 and compare them with global trends to provide insights for future prevention and control strategies.MethodsData were sourced from the Global Burden of Disease database 2021, which includes comprehensive information on the disease burden across 204 countries from 1990 to 2021. We analysed six key indicators: the mortality, prevalence, incidence, disability-adjusted life years, years lived with disability, and years of life lost. Age-standardized rates were analysed using the global age structure as a reference. Joinpoint regression was employed to assess the annual percentage change and average annual percentage change.ResultsIn 2021, 3.75 million prevalent breast cancer cases, with 385,837 new breast cancer cases and 88,106 deaths due to breast cancer, were reported from China. The crude rates of the prevalence, incidence, mortality, disability-adjusted life years, years lived with disability, and years of life lost significantly increased in 2021 compared with 1990. The age-standardized rates per 100,000 women were 355.72 for prevalence (+ 103.22% from 1990), 37.00 for incidence (107.40%), 8.24 for mortality (-8.24%), 281.54 for disability-adjusted life years (-6.68%), 25.86 for years lived with disability (110.24%), and 255.69 for years of life lost (-11.62%). The burden of breast cancer has notably increased among the women above 40 years of age, peaking between the ages of 50 and 59 years, and the proportion of cases in women under 40 years has decreased.ConclusionsThe age-standardized rate of the mortality, disability-adjusted life years, and years of life lost of breast cancer decreased slightly in China; however, the age-standardized rate of the incidence, prevalence, and years lived with disability exhibited an upward trend between 1990 and 2021, thereby highlighting the need to improve treatment outcomes and formulate better policies for the prevention and control of breast cancer in China.