Purpose: Some prostate cancer (PCa) patients become clinically anxious or depressed after diagnosis and treatment. Some also show the physiological signs of chronic stress. However, there are currently no data describing how these particular patients might be identified at intake. This study tested the individual and combined predictive power of a psychological factor and a genetic factor as potential predictors of anxiety, depression, and chronic stress in a sample of PCa patients. Methods: Ninety-five PCa patients completed psychological inventories for anxiety, depression, and psychological resilience (PR) and also gave a saliva sample for cortisol and a mouthwash sample for genetic testing for the presence of the BDNF Val66Met polymorphism. Results: High PR patients had significantly lower anxiety and depression than low PR patients, but showed no significant differences in their salivary cortisol. Carriers of the Met allele of the BDNF Val66Met polymorphism had significantly higher salivary cortisol concentrations than patients who did not carry this allele. Conclusions: Each of these two factors may provide valuable information regarding the vulnerability of PCa patients to anxiety, depression, or chronic stress. Suggestions are made for their inclusion in clinical settings.