Previous research has supported a sex difference favoring males on computer-related variables. This study examines the potential mediating effects of psychological sex typing on computer variables. One hundred twenty-five undergraduates were administered measures assessing sex typing, computer experience, computer attitudes, computer self-efficacy, and computer aptitude. When the effects of specific computer experience and sex-typing variables were removed using analyses of covariance, male/female comparisons on computer aptitude and self-efficacy variables were no longer significant. Participant sex as well as masculinity and several computer experience variables were significant in the computer attitude analysis. © 1990 Plenum Publishing Corporation.