This review aimed to identify measurement tools to assess dietary intake and physical activity (PA) among individuals with autism spectrum disorder (ASD) and describe the evidence of validity and availability of each tool. Searches were conducted in PubMed, Embase, CINAHL, and PsycINFO using keywords for ASD, PA, diet, and assessment/measurement (n = 2364 articles). After removing duplicates and title/abstract screening, 212 full-text articles were reviewed, and 113 articles were included for data extraction. The most common dietary and PA assessment tools were identified, and each reviewer independently extracted the data on target population of the assessment tool, type of instrument, evidence on psychometrics validation, constructs measured, and instrument availability. Our findings highlight the need for instruments developed for and/or validated in this population.