Objective To explore the trend in self-management efficacy and exercise compliance among patients within 6 months after radical resection of lung cancer and analyse the predictive correlation between the factors to provide references for improvement of exercise compliance in patients after lung cancer surgery.Methods Convenience sampling was used to select patients who had surgery of radical resection of lung cancer for the first time in the departments of thoracic surgery of two Grade IIIA hospitals in Nanchong between December 2022 and May 2023.The Chinese-version strategies used by people to promote health(C-SUPPH)and exercise compliance scale were employed to assess the self-management efficacy and patient exercise compliance at four time points:1 day before discharge(T1)and 1 month(T2),3 months(T3)and 6 months(T4)after surgery.A cross-lagged model was constructed to analyse the causal correlation between self-management efficacy and exercise compliance.Results Within 6 months after surgery,both of self-management efficacy and exercise compliance in the patients after radical resection of lung cancer were seen initially increased and then decreased(P<0.05).The cross-lagged model revealed that self-management efficacy and exercise compliance during the early postoperative period(TI-T2)exhibited reciprocal causation(β=0.254,P=0.003;β=0.332,P=0.007).Between T2 and T3,higher self-management efficacy positively predicted an increased exercise compliance(β=0.286,P<0.001).However,during T3 and T4,no predictive relationship was observed between the indicators(P>0.05).Conclusion The self management efficacy of patients after lung cancer sugery is at middle level and their exercise compliance is at low level.This study indicates that the initial levels of self-management efficacy and exercise compliance among patients after radical resection of lung cancer do not necessarily reflect a long-term trend.The predictive correlation between the two factors also varies over the time.Healthcare providers should consider the dynamic changes and individual differences across different stages after surgery,and implement timely and targeted intervention.