The purpose of this study was to identify variables—that is, demographic factors (age, history of back pain, body mass index [BMI], and waist circumference), occupational stress, job satisfaction, perceived supervisor support, and physical fitness—that predict back pain in firefighters. Firefighters, an occupational group at high risk for back injury, perform many job tasks under hazardous work conditions. A nonexperimental, correlational design was used to study a convenience sample of 298 male firefighters who completed study questionnaires. Almost one third (30.20%) of the firefighters reported current back pain. The set of factors that predicted current back pain in firefighters included occupational stress, age, history of back pain, and BMI—pseudo R2 = .351. Further studies should validate the model and explore relationships among perceived supervisor support, occupational stress, and job satisfaction in other occupational groups, including nurses and police officers.