Background: Pragmatics has generally been defined as the ability to use language in social situations, it is commonly regarded as the third major component of language ability. To date, there is no tool for assessing early pragmatic development of Chinese-speaking children. Aims: To describe the translation of the Language Use Inventory (LUI) from English to Mandarin Chinese and to report findings on the Chinese version's reliability, validity and developmental sensitivity. Methods & Procedures: The original English version of the LUI was translated into Mandarin Chinese. Parents of 177 typically developing (TD) toddlers and preschool children completed the inventory to examine its internal reliability and construct validity and how scores differed across ages and sexes. A total of 31 parents out of the 177 completed the LUI-Mandarin, again within 4 weeks, to assess test-retest reliability. To examine discriminative validity, 43 parents of age- and sex-matched TD children and children with autism spectrum disorder (ASD) recruited from Nanjing Brain Hospital affiliated with Nanjing Medical University completed the LUI-Mandarin. Outcomes & Results: Cronbach's alpha values for the LUI-Mandarin's three parts and for 11 of 12 LUI-Mandarin subscales were 0.707-0.992, with most values in the 0.825-0.992 range. Test-retest reliability ranged from 0.66 to 0.95, indicating good to excellent reliability. Factor analysis of the LUI-Mandarin revealed two different factors, and the total variance explained was 74.38%. The LUI-Mandarin total scores and subscale scores increased with age for both boys and girls, providing evidence of the inventory's developmental sensitivity. Girls, however, had higher total scores than boys at earlier ages (18-23 months). The results of the discriminant validity study revealed that performance was significantly lower in the ASD group than in the TD group with respect to LUI total scores and subscale scores (except for subscale A). Conclusions & Implications: The LUI-Mandarin is the first and only questionnaire available in China that evaluates the pragmatic language skills of children aged between 18 and 47 months. The results of the study show that the LUI-Mandarin is a valid and reliable tool for Chinese toddlers and preschool children.