Objective To retrieve, evaluate and synthesize the best evidence on psychological prehabilitation for adult cancer patients at home and abroad, so as to provide a basis for clinical practice. Methods According to the "6S" evidence model, a top-to-down systematic search was conducted in clinical decision support systems, domestic and international guideline websites, professional society websites, and domestic and foreign databases to obtain relevant evidence on psychological prehabilitation for adult cancer patients, including clinical decisions, best practices, guidelines, evidence summaries, systematic reviews, and expert consensus. The search period was from the establishment of the database to August 2025. Results A total of 26 articles were finally included, consisting of 3 clinical decisions, 6 evidence summaries, 8 guidelines, 8 systematic reviews, and 1 randomized controlled trial. Twenty pieces of best evidence were summarized from five aspects:management principles, screening and assessment, psychological intervention, health education, and family support. Conclusion The summarized best evidence on psychological prehabilitation for adult cancer patients can provide an evidence-based foundation for preoperative psychological prehabilitation in this population. In clinical application, full consideration should be given to the applicability of clinical scenarios and patient needs to develop scientific, feasible, and personalized psychological prehabilitation programs.