Anxiety is highly prevalent in individuals with ASD with lifelong impact. In this population, anxiety often emerges when children are very young, yet there are no evidence-based treatments for this age group. Cognitive-behavioral treatment (CBT) successfully reduces anxiety levels in young, typically developing children and older children with ASD. This study pilots the DINO Strategies for Anxiety and fear of Uncertainty Reduction (DINOSAUR) program, which is an integrated treatment program that utilizes CBT modified for young children with ASD. The treatment includes heavy doses of parent training to reduce accommodation of the child's anxiety symptoms and interventions targeting fear of uncertainty, a common fear in children with ASD. The feasibility, acceptability, and preliminary efficacy of this treatment program will be studied.