BACKGROUND The co-occurrence of physical inactivity and poor mental health in the college student population can lead to chronic health issues that have negative short-term effects (e.g., academic success). Poor mental health is associated with long-term conditions (e.g., obesity, serious mental illness) that are linked to premature mortality. The purpose of this study was to examine the information-motivation-behavioral (IMB) skills model and evaluate its ability to explain the variance in the use of exercise prescription in mental health treatment. METHODS Mental health professionals (MHPs) (n = 255) were recruited from college counseling centers in the USA. Structural equation modeling was used to examine the relationship between the predictor variables of information (exercise knowledge and benefits of exercise), motivation (personal beliefs, perceived barriers, and organizational support), and behavioral skills (self-efficacy), and the outcome variable of exercise prescription (i.e., brief counseling and referral for exercise). RESULTS The predictors accounted for 23% of the variance in exercise prescription (p = .001). Organizational support had a significant direct effect on exercise prescription (β = 0.27, p = .05). Personal beliefs (β = 0.96, p = .05) and organizational support (β = 0.31, p = .04) had significant direct effects on self-efficacy for prescribing exercise. MHP personal exercise behavior was associated with exercise prescription. CONCLUSIONS MHPs may be willing to support physical activity promotion and exercise prescription, but organizational structures are critical to enhance and sustain the delivery of this adjunctive therapy. The personal exercise history of MHPs may be an important consideration for behavior change interventions. The development and validation of scales are important considerations for future intervention study design.