To explore the trajectories of acceptance of disability in young and middle-aged breast cancer patients based on a latent class growth analysis, investigate factors associated with each trajectory, and identify whether return to normal living differs in different trajectories. Young and middle-aged patients newly diagnosed with breast cancer who underwent surgery were followed up at baseline, and 1, 3, and 6months in China. Participants completed sociodemographic information questionnaires, the Adaptation of Disability Scale Revised, and the Reintegration to Normal Living Index. A latent class growth analysis was used to explore the trajectories of acceptance of disability. Among 212 patients newly diagnosed with breast cancer, the mean age of patients was 45.44years. The majority of participants were with invasive carcinoma (77.8%). Three classes were identified: high acceptance of disability increasing group (high-increasing, 13.7%), moderate acceptance of disability stable group (moderate-stable, 67.9%), and moderate acceptance of disability decreasing group (moderate-decreasing, 18.3%). Being unemployed or retired and receiving endocrine therapy are risk factors associated with acceptance of disability. Carcinoma in situ is a protective factor associated with acceptance of disability. Participants diagnosed with carcinoma in situ and who not receive endocrine therapy were more likely to be in high-increasing group. Unemployed participants before surgery were more likely to be in moderate-decreasing group. Moreover, the Reintegration to Normal Living Index scores had significant differences from baseline to 6months of follow-up. The high-increasing group had the highest average Reintegration to Normal Living Index scores than the moderate-stable group and the moderate-decreasing group, showing similar patterns at four timepoints. We identified three trajectories of acceptance of disability. Dynamic and individualized intervention should be continuously provided to ensure patients acquire adequate medical resources to comprehensively increase acceptance of disability.