Because early intervention often leads to the best outcomes in children with autism spectrum disorder (ASD), it is important that these children are identified as early as possible. Therefore, exploration of tools that could be used to identify at-risk children at an early age is needed. Such a tool could assist health professionals and their decision about whether to refer an individual for a full diagnostic assessment for ASD. Several studies have demonstrated and supported the use of screening algorithms created from measures of developmental functioning. The purpose of the current study was to explore the relationship between a measure of developmental functioning and screening outcome in infants and toddlers screened for ASD. Participants were 13,781 infants and toddlers screened for ASD. Results demonstrated that the Battelle Developmental Inventory, Second Edition (BDI-2) Total Developmental Quotient and Domain scores were statistically significant predictors of screening outcome for both younger and older infants and toddlers. This suggests that the BDI-2 can be a useful tool in the screening of ASD among infants and toddlers seeking and/or receiving early intervention services.