Speech therapists make use of the knowledge of linguistics to describe, analyze and make diagnoses on language samples of patients suffering from communication disorders. Clinical linguistic investigation aims at improving the therapeutic process and the analysis of disordered speech/language samples. Patients with autism spectrum disorder (ASD), whose deficits are hypothesized to originate from pragmatic deficits, require both linguistic knowledge as well as a theory of mind (ToM) to test the truthfulness of the hypothesis. Substantial studies have investigated autistic individuals’ linguistic and theory of mind (ToM) abilities, with mixed results. Issues under debate include which particular aspects of language individuals with ASD have difficulties with, and how they relate to ToM development. Compared to studies on linguistic abilities in English-speaking children with ASD, relatively little is known about linguistic abilities in Chinese-speaking children with ASD. Chinese, a topic prominent language, is typologically different from English. Among various aspects of language, syntax is important as it functions as a bridge to connect morphology and semantics. In addition, the important role of syntax has also been found in typically developing (TD) children’s ToM development. Taking into account specific syntactic features in Chinese, the present study investigates syntactic and theory of mind (ToM) abilities in Cantonese-speaking autistic children. Can-LARSP analysis indicates that autistic children had less well-developed syntactic ability than their MLUw-matched TD peers. Autistic children’s ToM performance indicates that the majority passed the 1st-order FB tasks, while most of them failed the 2nd-order FB task. Comparisons of syntactic abilities between the groups indicate that those who passed had more well-developed syntactic abilities than those who failed, suggesting that autistic children may be chronologically and linguistically delayed in ToM, and their syntactic ability may positively relate to their ToM development.