Objective To explore the effect of perioperative refined nursing on scar appearance and breast aesthetic effect in breast cancer patients undergoing immediate oncoplastic breast-conserving surgery. Methods A total of 82 breast cancer patients who underwent immediate oncoplastic breast-conserving surgery at the Cancer Hospital of General Hospital of Ningxia Medical University from February 2023 to October 2025 were selected as the research subjects. According to the random number table method, they were divided into the control group and the observation group, with 41 patients in each group. The control group received conventional perioperative nursing, and the observation group received perioperative refined nursing. The clinical relevant indicators, scar appearance, nipple deviation and breast aesthetic effect were compared between the two groups. Results The drainage tube indwelling time and hospitalization time of the observation group were shorter than those of the control group (P <0.05). The scar score of the observation group at 3 months after operation was lower than that of the control group (P <0.05). The scores of horizontal and vertical nipple deviation distance in the observation group at 3 months after operation were higher than those in the control group (P <0.05). The excellent and good rate of breast aesthetics in the observation group (90.24%) was higher than that in the control group (68.29%) (P <0.05). Conclusion For breast cancer patients undergoing immediate oncoplastic breast-conserving surgery, the application of perioperative refined nursing can shorten drainage indwelling time and hospitalization time, ameliorate scar formation, reduce horizontal and vertical nipple deviation, and improve postoperative breast aesthetic effect.