Purpose <p>The ability to understand emotional prosody is directly relevant to effective social communication. Typically developing (TD) children at age 3 start to understand emotional prosody in both native and foreign languages, but it remains unclear whether autistic children demonstrate a similar pattern. To address this, this study examined Mandarin-speaking autistic children’s understanding of two basic emotional prosody, happy and sad, across languages.</p> Methods <p>We manipulated the language where emotional prosody was presented: familiar (Mandarin) versus unfamiliar (French and Spanish). Autistic 3- and 5-year-olds and age-matched TD children completed a face-sound matching task where they were asked to point at the emotional face that matched the spoken sentence they heard.</p> Results <p>Autistic children exhibited similar patterns to age-matched TD peers in the native language condition but showed significantly lower accuracy when responding to emotional prosody in foreign languages. Importantly, however, autistic children’s performance across all language conditions was above chance, and within-group analysis showed that they performed better in the native language condition than in the foreign language conditions.</p> Conclusion <p>These findings suggest that autistic children can decode emotional prosody across languages, although their ability to process emotional prosody in foreign languages is less developed than TD children. This pattern might reflect fundamentally different mechanisms between the two groups. Alternatively, it could also be explained by shared mechanisms between the two groups, with the difference reflecting autism-related neurocognitive characteristics constraining autistic children’s processing efficiency. In addition, the native language advantage can be leveraged to support emotional communication in autistic children.</p>