Background <p>Prehabilitation improves functional capacity and, thus, treatment outcomes and quality of life through physical, nutritional, and psychosocial interventions prior to the start of treatment. While physical and nutritional interventions are well established, psycho-oncological components remain underrepresented.</p> Objective <p>This review systematizes the current evidence on psycho-oncological prehabilitation and derives practical recommendations for clinical integration.</p> Methods <p>Narrative review based on current systematic reviews, meta-analyses, and clinical studies.</p> Results <p>Psycho-oncological interventions work through several synergistic mechanisms: Emotional stabilization reduces anxiety and improves cognitive processing of medical information. Strengthening self-efficacy increases adherence to medical interventions by 30–40%. Realistic expectation management reduces treatment discontinuation, while social resource activation supports coping. Multimodal programs consistently show superior results compared to unimodal approaches: significant anxiety reduction, improved quality of life, and 20–30% greater improvements in functional capacity. Standalone psycho-oncological prehabilitation is indicated in cases of pronounced distress, physical limitations, or limited time frames.</p> Conclusion <p>Psycho-oncological prehabilitation is effective and should be routinely integrated into multimodal programs. Implementation requires structural prerequisites and methodologically robust research on long-term effects and cancer entity-specific adaptations.</p>