BACKGROUND:In early typical language development, children understand words before they are able to use them in speech. Children with autism spectrum disorders (ASD) generally show impairments in both the comprehension and the production of language. However, the relative degree of delay or impairment in each of these sub-domains may also be atypical and remains less well-understood. AIMS:Relative delay in receptive and expressive language skills was examined within a large sample of preschoolers with autism. Children's language abilities varied from pre-verbal to fluent speech. METHOD & PROCEDURES:Scores on one direct clinician assessment and two parent-report measures of language were obtained for 152 preschoolers with core autism. OUTCOMES & RESULTS:As expected, on average, the language ability of the children with autism was lower than typical age norms, albeit with substantial individual variability. On all three language measures, receptive ability was relatively more impaired than expressive ability. Higher non-verbal ability was associated with such an atypical language profile. CONCLUSIONS & IMPLICATIONS:Recognition of the marked receptive language impairment relative to expressive language, found to affect at least one-third of preschoolers with autism in this sample, has important implications for interacting with these children and for informing appropriate targets in language and communication intervention.