We examined the communicative intentions behind parents' deictic gesture use with high-risk infants later diagnosed with autism spectrum disorder (ASD; n = 17), high-risk infants who were not diagnosed with ASD (n = 25), and low-risk infants (n = 28) at 12 months and assessed the extent to which the parental deictic gesture intentions predicted infants' later vocabulary development. We found that parents in the three groups produced similar numbers of declarative and imperative gestures during a 10-minute parent-child interaction in the lab at 12 months and that 12-month parental declarative gesture use was significantly, positively associated with children's 36-month vocabulary scores. Encouraging parental use of declarative gestures with infants could have important implications for language development.