Background: Sentence Repetition (SR) is considered to be a good indicator of children’s grammatical knowledge. Cross-linguistic evidence suggests that performance on SR improves with age, differentiates children with language difficulties, and shows relationships with other language assessments. However, there is debate about the underlying skills involved in SR with few studies directly investigating the impact of linguistic manipulation on SR performance. In the absence of standardized language assessments and lack of normative data, and building on evidence from typologically diverse languages, SR provides a potentially useful assessment tool in Arabic. Aims: (1) To examine the clinical utility of a novel SR test and an adapted Verbal Short Term Memory (VSTM) test by investigating the psychometric properties of the tests and their sensitivity to age and language ability. (2) To evaluate the contribution of established linguistic knowledge to immediate repetition by comparing the patterns of performance across different linguistic factors 3) To determine whether patterns of performance are similar or dissimilar across different age groups of Typically Developing children and different language ability groups. Methods: Three immediate repetition tests were developed or adapted: (1) a novel SR test targeting morphosyntactic structures of Arabic; (2) an adapted VSTM test based on the structure of the Working Memory Test Battery for Children (WMTB-C; Pickering & Gathercole, 2001) with three subtests of Digit Recall, Word List Recall, and Nonword List Recall; and (3) an Anomalous Sentence Repetition (ASR) test including sets of Semantically Anomalous and Syntactically Anomalous sentences created from and matched to a subset of sentences in the SR test in target Lexical and Grammatical Morphemes as well as length. The SR and ASR tests were scored for the number of Lexical and Grammatical Morphemes repeated correctly. VSTM tests were scored based on the highest number of items repeated in correct order. The SR and VSTM tests were administered to Typically Developing Arabic-speaking children aged 2;6 to 5;11 (n = 140) and a Language Concerns group in the same age range (n = 16), matched on age and nonverbal IQ. The ASR test was only administered to participants older than 4 years. Results: The SR and VSTM tests were reliable, valid, and sensitive to age and language ability of participants. In the Typical sample a) Lexical Morphemes were easier to repeat than Grammatical Morphemes, (b) Digit span was higher than Word span and Word span was higher than Nonword span, and (c) Typical sentences were easier to repeat than Semantically Anomalous sentences followed by Syntactically Anomalous sentences. The gap between Digit and Word span, Grammatical and Lexical Morphemes in the SR test and Lexical Morphemes in Typical and Semantically Anomalous sentences showed a change with age. While performance was significantly reduced in the Language Concerns group, the profile of performance was largely similar. Like the younger children in the Typical sample, they showed a greater vulnerability in Grammatical Morphemes. Only four of 16 children in the clinical sample showed mismatches between their performance on the SR and VSTM tests. Conclusions: The study’s results are consistent with cross-linguistic evidence demonstrating that SR and VSTM tests are sensitive to developmental change and language difficulties and are informative about children’s language processing abilities. These findings lay the foundations for creating standardized assessments for Arabic-speaking preschool children.