Atypical sensory processing is common in autism spectrum disorders (ASD), but their role in adaptive difficulties and problem behaviors is poorly understood. Our aim was to determine the prevalence and type of atypical sensory processing in children with ASD and investigate its impact on their adaptive functioning and maladaptive behaviors. We studied a subsample of 197 children rigorously diagnosed with ASD from the ELENA cohort. Children were divided into atypical and typical sensory processing groups and several independent variables were compared, including adaptive functioning and maladaptive behaviors. Overall, 86.8% of the children had at least one atypical sensory pattern and all sensory modalities were disturbed. Atypical sensory processing explained a significant part of the variance of behavioral problems.