Abstract Importance: Assessment of praxis skills is an essential aspect of understanding autistic children’s development of play and playfulness. Objective: To assess the relationship and influence of ideational praxis skills on play skills and playfulness among autistic children. Design: A cross-sectional study. Settings: Homes, schools, and early care centers across Spain. Participants: Children ages 4 yr 6 mo to 6 yr 11 mo (45 typically developing [TP] and 45 with autism spectrum disorder [ASD]). Outcomes and Measures: Student’s t tests were used to compare means between the two groups. Pearson’s correlation and multiple linear regression were used to determine possible effects of ideational skills on play and playfulness. Results: Scores for the TP group were significantly higher than those of the ASD group on all play dimensions—space management, t(88) = 4.58; material management, t(88) = 5.86; pretense–symbolism, t(88) = 8.12; and participation, t(88) = 7.31—and on the Test of Playfulness (ToP), t(88) = 10.18, and Test of Ideational Praxis (TIP), t(88) = 4.38 (all ps < .001). Multiple linear regression revealed a statistically significant effect of TIP dimensions—space management, F(3, 41) = 4.83, p < .042; material management, F(3.41) = 8.49. p < .001; pretense–symbolism, F(3, 41) = 5.66. p < .002; and participation, F(3.41) = 7.81. p < .001—and on the ToP, F(3, 41) = 5.96. p < .002. Conclusions and Relevance: Ideational praxis skills combined with diagnostic information significantly predicted play skills and playfulness, highlighting the influence of ideation on play. Plain-Language Summary: This article provides data supporting the influence of ideational praxis skills on the play skills and playfulness of autistic children. Understanding how ideational praxis skills affect the ability to recognize and act on object affordances might promote greater possibilities for play interactions among autistic children.