The study aims to explore the effect of nursing intervention based on risk assessment model on self-efficacy and postoperative rehabilitation of surgical patients. The study applied a risk assessment model to the behavioral intervention of rehabilitation exercise in patients after percutaneous coronary intervention (PCI). A total of 157 patients were selected from a certain hospital, with 52 cases in the experimental group and 55 cases in the control group. A comprehensive cardiac rehabilitation intervention strategy based on TTM is given by researchers trained with professional knowledge, including dividing the stages of behavior change, developing a rehabilitation exercise plan through exercise teaching and exercise training, diet and lifestyle guidance, and urging patients to take regular medication and regular follow-up. The stage of rehabilitation movement behavior change improved. The preexperiment health status was (35.39 ± 14.31), and the overall health of the control group was (32.59 ± 15.41). Overall health status and QOL scores were relatively low in both the groups. The intervention group scored higher than the control group. After coronary stent implantation, the heart restores its original pumping function, various organs and tissues receive effective blood perfusion, and the symptoms of myocardial infarction such as profuse sweating, dizziness, fatigue, and precordial discomfort are effectively relieved. The physical discomfort can gradually improve or even recover to the functional state before the onset of the disease. Before the intervention, the self-efficacy score of the intervention group was (23.68 ± 4.49). After the intervention, the self-efficacy score of the intervention group was (26.21 ± 4.09), while the self-efficacy score of the control group before the intervention was (22.21 ± 4.1). After the intervention, the self-efficacy score of the control group was (25.23 ± 4.41). Although the self-efficacy score of the control group was improved, the difference was small, and the intervention effect was not obvious. It indicates that risk assessment intervention can improve patients' self-efficacy level and quality of life of postoperative rehabilitation patients.