Background: There has been a worldwide reported increase in the prevalence of Autism spectrum disorder (ASD). There is also an international recognition of the value of early diagnosis and intervention of children with ASD. A lack was identified in the literature in KSA regarding assessing ASD knowledge among medical consultants. Aims: firstly, to assess ASD knowledge among medical consultants in KSA. Secondly, to investigate if there is any differences between medical consultants based on their years of experience and subspecialties. Method: KCAHW questionnaire was utilized to collect data from 53 consultants at a university hospital in KSA. Results: the level of ASD knowledge among medical consultants in KSA was low. Moreover, years of practice as consultants were discovered to be non-significantly correlating with ASD knowledge. Finally, the level of ASD knowledge was significantly affected by subspecialties in all the domains of KCAHW. Conclusion: more formal training on ASD and the integration of it in medical curriculum is needed to increase the level of knowledge in medical staff for early and better detection of ASD.