While sex differences in play have been extensively observed in typical development, only a handful of studies have explored this phenomenon in depth with children with autism spectrum disorders. This study explored sex differences in play complexity and toy engagement within caregiver–child interaction samples for preschool-aged children (2–5 years 11 months) with an autism spectrum disorder who were matched to typically developing children on sex and non-verbal development. Overall we found that girls and boys with autism spectrum disorder were largely equivalent in their play complexity. Despite similar play, girls and boys with autism spectrum disorder differed in a number of ways in their toy engagement, replicating traditional gender differences—girls played more with dolls and domestic items (though at lower rates than typically developing girls) and boys played more with the garage and cars (though at lower rates than typically developing boys). Our findings support the importance and utility of examining sex differences in autism spectrum disorder in light of those observed within typical development.