With the continuous improvement of long-term survival rates among solid organ transplantation (SOT) recipients, de novo malignancy (DNM) following transplantation have become a critical factor impairing long-term prognosis and causing non-organ-failure-related mortality. The risk profile and disease spectrum of DNM vary across different types of SOT recipients, modulated by multiple factors including ethnicity, primary underlying diseases, intensity of immunosuppression, regional environmental conditions, and patterns of viral infection. Distinct differences exist in demographic characteristics and cancer epidemiology between Chinese SOT recipients and their Western counterparts, rendering overseas evidence and recommendations not fully applicable to clinical practice in China. Against this backdrop, the Organ Transplantation Rehabilitation Committee of Chinese Association of Rehabilitation Medicine convened multidisciplinary experts to formulate the Clinical Practice Guidelines on De Novo Malignancies After Solid Organ Transplantation in Adult in China. Integrating domestic and international evidence-based medical data alongside real-world clinical experience in China, this guideline proposes clinical recommendations for risk assessment, screening, surveillance and management of post-transplant DNM specifically tailored to adult Chinese SOT recipients, so as to provide evidence-based references for clinical identification, monitoring and standardized management of DNM in this population.