This study aimed to evaluate the effect of the 4C continued care model (refers to the nursing services of comprehensiveness, coordination, continuity and collaboration) in the continued care of breast cancer patients and its impact on postoperative complications. 180 breast cancer patients were divided into the conventional nursing group, and the 4C continued nursing group. The patient’s mental state, self-efficacy, self-care ability, quality of life, nursing satisfaction, and the occurrence of postoperative complications under the two nursing modes before care and two months after discharge were compared. The self-rating anxiety scale (SAS) and self-rating depression scale (SDS) scores of patients in the 4C continued care group were significantly lower than those of the conventional care group two months after discharge. The self-efficacy and self-care ability scores were significantly higher than those of the conventional care group. The scores in the five dimensions of quality of life were significantly higher than those of the conventional care group, and the differences were all statistically significant (p < 0.05). Satisfaction with care was also significantly higher in the 4C continued nursing group compared to the usual care group (93.33% vs. 81.11%, p < 0.05). The overall adverse event rate of subcutaneous effusion and lymphedema was significantly lower in the 4C continued care group (22.22% vs. 48.89%, p < 0.001). The clinical effect of the 4C nursing model of postoperative care of breast cancer patients was significant. The 4C nursing model can effectively improve patients’ mental state, self-efficacy, self-care ability, quality of life and nursing care satisfaction, and reduce the occurrence of postoperative adverse reactions.