Path analysis was used to test the influence of writing self-efficacy, writing apprehension, perceived usefulness of writing, and writing aptitude on the essay-writing performance of 218 fifth-grade students, A model that also included sex accounted for 64% of the variance in performance, As hypothesized, self-efficacy beliefs made an independent contribution to the prediction of performance despite the expected powerful effect of writing aptitude, Aptitude also had a strong direct effect on self-efficacy, which mediated the indirect effect of aptitude on performance. Self-efficacy had direct effects on apprehension and perceived usefulness. Girls and boys did not differ in performance, but girls reported higher writing self-efficacy, found writing more useful, and had lower apprehension, Results support the hypothesized role of self-efficacy in Bandura's (1986) social cognitive theory.