This investigation examined the moderating effects of physical health and scripts for masculinity (i.e., self-reliance and emotional control) on the relationship between powerful other people locus of control and mental health for 230 men treated for prostate cancer. Regression analyses indicated that physical health and masculine gender scripts moderated the association between powerful other people locus of control and mental health. Specifically, men with poor physical health evinced negative mental health when they endorsed masculine gender scripts and believed powerful other people (i.e., family, friends, or peers) were influential in controlling their cancer. By comparison, men reporting poor physical health, strong beliefs that powerful other people controlled their cancer, and less adherence to masculine scripts experienced positive mental health. The authors discuss future research directions and potential mental health implications for men treated for prostate cancer.