Few instruments screen for autism spectrum disorder (ASD) among kindergarteners and older children. The Autism Screen for Kids and Youth (ASKY) is a 30-item parental questionnaire for 4- to 18-year-old children and adolescents available in Arabic, English, and Hebrew. We examined the sensitivity, specificity, and temporal stability of the Hebrew ASKY’s categorizations (“probable ASD” versus “probable non-ASD”) of 167 autistic and non-autistic 4- to 18-year olds. Algorithm-based categorization following The Diagnostic and Statistical Manual of Mental Disorders: Fifth Edition ( DSM-5) rules demonstrated 91.8% sensitivity, 71.7% specificity, and excellent test–retest reliability (κ = 0.783, 95% confidence interval (CI) = 0.583–0.983, p < 0.001). Total score-based categorization using a cutoff of 9 demonstrated high receiver operating characteristics area under the curve (AUC = 0.874) and high sensitivity (93.4%), specificity (78.3%), internal consistency (Cronbach’s α = 0.954), and test–retest reliability (κscores = 0.674, κinstrument = 0.783). Discussing both categorization approaches, we show that the ASKY is a promising instrument for ASD screening of older children. Lay Abstract It is important that autistic children be diagnosed as early as possible so their needs can be met and their families can gain important insights into their behavior and interact with them appropriately. However, very few autism screening instruments are appropriate for children who have outgrown early childhood. The Autism Screen for Kids and Youth (ASKY) presents parents of children aged 4–18 years with 30 items that relate to autistic behaviors as defined by the current clinical diagnostic criteria for autism spectrum disorder ( DSM-5 ASD). We evaluated the Hebrew instrument’s performance on 167 autistic and non-autistic children and adolescents. We found that the ASKY algorithm correctly identified 92% of the autistic individuals as “probable ASD” and correctly identified 72% of the non-autistic individuals as “probable non-ASD,” with these classifications showing excellent stability over time. Using total questionnaire score instead of the algorithm improved the ASKY’s ability to correctly identify autistic individuals as “probable ASD” and non-autistic individuals as “probable non-ASD” to 93% and 78%, respectively. Overall, the ASKY is a promising instrument for ASD screening of older children.