To explore the effect of evidence-based nursing in preventing scar hyperplasia after scar plastic surgery. Methods A total of 80 patients with scar plastic surgery admitted to Zhongda Hospital Affiliated to Southeast University from February 2020 to February 2022 were selected as the research objects. The patients were divided into experimental group and conventional group by random number table method, with 40 patients in each group. The conventional group was given conventional nursing intervention, and the experimental group was given evidence-based nursing intervention. The Vancouver Scar Scale score, the incidence of pigmentation, emotional indicators [Self-rating Depression Scale (SDS) and Self-rating Anxiety Scale (SAS)] and nursing service satisfaction were compared between the two groups. Results The Vancouver Scar Scale score of the experimental group was lower than that of the conventional group at 1 week and 1 month after intervention, and the incidence of pigmentation was lower than that of the conventional group (P <0.05). After the intervention, the SAS score and SDS score of the two groups were lower than those before the intervention, and those in the experimental group were lower than those in the conventional group (P <0.05). The nursing satisfaction rate of the experimental group was 90.00%, which was higher than 80.00% of the conventional group (P <0.05). Conclusion Evidence-based nursing intervention after scar plastic surgery can not only effectively prevent the formation of scars, improve skin aesthetics, but also improve the physical and mental state of patients and improve the evaluation of nursing services, which is worthy of clinical application.