The study investigated the Influence of Environmental Supports on Learning Outcomes among Learners with Autism Spectrum Disorders in Special School Setting in Kenya.The study population comprised 420 teachers and 30 head teachers, 30 deputy head teachers and 360 teachers in the 30 selected special schools in the North Rift and Western regions of Kenya. The study used convergent parallel mixed methods design. The sample size for this study comprised 200 teachers from 25 schools. Simple random and purposive sampling was used to sample the participants. Data was collected through a survey comprisingself-administered questionnaires; in-depth interviews, and classroom observations. Face and construct validity was ensured using expert judgment by university supervisors while reliability was ensured by split-half method and an r=0.858 was reported. Quantitative data was analyzed using descriptive statistics and also inferential statistics such as Pearson Correlation and Regression analysis. Qualitative data on the other hand was analyzed by using thematic framework. Reliability wasdetermined by internal consistency and a reliability coefficient of r=0.752 was reported.The finding of the study shows that there was statistically significant, but weak positive correlation (r=.411, n=138, p<.05) between use of environmental supports and overall learning outcomes, with the improved use of environmental supports causing improvement of overall learning outcomes.The study recommends that the Kenya Institute of Curriculum Development (KICD) and the Universities should ensure that courses offered in teacher preparation programmes are focused on relevant courses addressing education of learners with autism.