This study investigates the status of biofeedback treatment and locus of control (LOC) affiliation on the reduction of tension headache. Three LOC groups designated as internals, powerful-other externals and chance externals (using Wallston and Wallston's, 1978, Multidimensional Health Locus of Control Scale) were administered an eight week electromyogram (EMG) frontalis muscle biofeedback training program using an Autogen 1700 biofeedback unit. Subjects were 12 female and four male undergraduate students who had a history of tension headache. Results indicated no significant difference in frontalis muscle tension between the beginning and end of sessions in either a biofeedback or self-control condition for any of the LOC groups. Further, there was no significant difference among LOC groups in ability to reduce muscle tension in either the training or self-control condition. Finally, neither biofeedback training nor LOC groups were significant predictors of headache reduction. Extreme within-group variability and small sample size affected study findings and these and other implications for future research are discussed.