Objective Prostate cancer is the most common cancer in German men and associated with various physical and psychosocial problems. This study investigated the association between mental distress and the subjective need for psychosocial support comparing subgroups of patients with different treatments and disease stages. Method We performed an observational, cross-sectional study including patients with four medical conditions: Active Surveillance, radical prostatectomy, biochemical relapse, metastasized disease. Mental distress (NCCN Distress-Thermometer), symptoms of depression and anxiety (PHQ-9, GAD-7), psychosocial needs and coping resources (self-designed questionnaire) were assessed. Results N = 130 patients were included. 33.3% showed distress, 16.5% symptoms of moderate depression and 13% symptoms of moderate anxiety. We found no significant differences between the four groups. An association was present between distress and wish for psychosocial support ( χ2 = 4.3; p < 0.05; ϕ = 0.19). Almost 90% lived with a partner, which represents a resource. Conclusions Prostate cancer patients showed low levels of mental distress, depression and anxiety with no difference in terms of disease stage and treatment modality. Therefore, careful psychosocial screening of all patients is essential to identify those in need for support. Distressed patients express a need for psychosocial support more often. Interpersonal relationships, most often wives and children, represent important coping resources.