This research paper aimed to provide an awareness study about teacher’s knowledge of Autism Spectrum Disorder (ASD) and their perception of interest and perceived efficacy in working with ASD children in Kota Kinabalu, Sabah. In addition, the purpose of this study also to examine the relationship between teacher’s knowledge of ASD and their perception. Methodology of this research is based on a survey of 240 questionnaires, which is given to each teacher from 6 selected primary schools in Kota Kinabalu, Sabah. The data collected were then analyzed by using the SPSS (Version 23), using Pearson’s correlation test to study the hypotheses that had been developed. The results showed a significant positive correlation between teachers’ knowledge of ASD and their perception of interest and perceived efficacy in working with ASD children. Thus, findings of this study concluded that there is still lack of awareness regarding of ASD in Kota Kinabalu, Sabah. Therefore, researcher suggested that it is important in the future for every school to implement a basic courses, proper training, workshops or related seminars for their teachers, as based from the present study showed that teachers have a quite high perception of interest and perceived efficacy in working together with ASD children.