The Myers-Briggs Type Indicator and the Anxiety Sensitivity Index were administered to 143 undergraduate college students. Analyses of variance were performed to assess the relationship between these indices and semester grades (Grade Point Average). The Myers-Briggs Sensing-Intuitive and Judging-Perceiving dimensions showed significant main effects on GPA. The interaction of Judging-Perceiving and Anxiety Sensitivity was also significant (F = 18.00, p < .0001), although that of Sensing-Intuition and Anxiety Sensitivity was not ( F = 3.51, p = .06). These findings suggest that personality factors measured by the Myers-Briggs Type Indicator may serve as mediating variables in evaluating whether trait anxiety has a facilitating or debilitating effect on academic achievement.