The purpose of this pilot study was to determine the effect of teacher professional development for working with students with Autism Spectrum Disorders and teacher (N = 56) self-efficacy in the general education classroom. A pretest/posttest quasi-experimental research design was implemented. Teachers in one randomly assigned school received professional development training on research-based practices in working with students with autism to determine if the training had any effect on their perceived self-efficacy ratings and teachers in the other school were randomly assigned to serve as the control (i.e., no additional professional development training was provided during the research phase). Results showed that the training had a large positive effect on teacher self-efficacy ratings regarding working with students with autism in the inclusion classroom. Findings tentatively show the need and importance for the provision of more professional development training to general education teachers for working with students with autism to improve teacher self-efficacy and to provide the most effective and inclusive educational experience possible.