Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder characterized by deficits in social communication and the presence of restricted, repetitive behaviors. It can be difficult to model the complex behavioral features of this disorder with rodent models, which have limited similarity to human behaviors. The domestic dog may be a promising model of complex human behavior, including core features of ASD. The present study examines ASD-relevant social behavior in Miniature and Standard Poodles using an owner-report questionnaire with questions adapted from the Autism Diagnostic Observation Schedule (Lord, Rutter, DiLavore, & Risi, 2000). A previous study identified 3 behavioral constructs examined by this questionnaire: initiation of reciprocal social behaviors, response to social interaction, and communication. In the present study, confirmatory and experimental factor analyses used to assess how collected data fit with the previous model revealed moderate model fit and a similar factorial structure. Between-breed comparisons across these factors and at the individual question level revealed differences between Miniature and Standard Poodles in showing behaviors. Cluster analyses used to group dogs within each breed according to social behavior identified smaller subgroups of dogs with less social behavior across all 3 factors compared with the average within each breed. Within- and between-breed differences in social behavior warrant investigation of genetic variation underlying this complex trait as it relates to ASD-relevant behavior.