Objective To explore the effect of nursing intervention based on positive psychology theory on patients with scar plastic surgery after facial burn and its influence on wound condition. Methods From May 2022 to May 2023, 80 patients with scar plastic surgery after facial burn in our hospital were selected as the research objects. According to the random number table method, they were divided into the control group and the experimental group, with 40 patients in each group. The control group was given routine nursing, and the experimental group was given nursing intervention based on positive psychology theory on the basis of the reference group. The wound healing, psychological state, nursing satisfaction, coping style and quality of life were compared between the two groups. Results The wound healing time of the experimental group was shorter than that of the control group, the incidence of pigmentation and scar hyperplasia was lower than that of the control group (P <0.05). After intervention, the SAS score and SDS score of the experimental group were lower than those of the control group (P <0.05). The nursing satisfaction of the experimental group was 97.50%, which was higher than 80.00% of the control group (P <0.05). After intervention, the positive coping score of the experimental group was higher than that of the reference group, and the negative coping score was lower than that of the control group (P <0.05). After intervention, the scores of quality of life in the experimental group were higher than those in the control group (P <0.05). Conclusion The effect of nursing intervention based on positive psychology theory in patients with scar plastic surgery after facial burn is good, which can promote wound healing, improve the psychological state and quality of life of patients, help to improve their personal coping ability and improve nursing satisfaction. It is worthy of clinical application.