This study provides a preliminary validation of a Greek Sentence Repetition Task (SRT) with a sample of 110 monolingual and bilingual typically developing (TLD) children and examines the test's ability to distinguish between Greek monolingual children and age-matched Albanian-Greek bilinguals using a Receiver Operating Characteristics (ROC) analysis. This is the first study to report on the psychometric evaluation of a Greek SRT and its discriminatory ability with typical populations. Since most language assessments are standardized with monolinguals and bilingual children tend to underperform on these compared to monolinguals, it is essential to establish the level of bilingual TLD children's ability on the same tests before moving on to diagnose language impairment in bilinguals. Results showed that the Greek SRT had very high validity and reliability scores, with Accuracy measures being more reliable than Grammaticality measures. The school-age monolingual and bilingual TLD children reached different cut-off scores on this task.