A dyadic microanalysis approach was used to examine emotion coregulation processes in mother-child interactions in relation to children's maladaptive behaviors. Seventy-two mother-child dyads (46 children with Autism Spectrum Disorder (ASD); 26 neurotypical children) were previously videotaped in a semi-structured play procedure at home and mothers reported on children's internalizing and externalizing behaviors. Mother-child interactions were reliably coded in 5-second intervals and analyzed using Space State Grid software. Regression analyses supported moderation, whereby greater dyadic flexibility and more mutual-positive engagements were significantly associated with lower levels of maladaptive outcomes for children with ASD. Results have implications for initiating positive interactions and promoting effective parenting that help improve behavior in young children with ASD.