This article investigates verbal short-term memory (vSTM) and verbal working memory (vWM) abilities and their relation to lexical and syntactic abilities in monolingual (mono-) and bilingual (bi-) children with Developmental Language Disorder (DLD) and typical development (TD). The authors employed the following tasks: vSTM (non-word repetition and forward digit span), vWM (backward digit span), receptive vocabulary, syntactic production (sentence repetition) and syntactic comprehension (relative clauses, reflexives and passives). While the mono- and bi-DLD groups underperformed the mono- and bi-TD groups respectively in all tasks, the two clinical groups differed only in receptive vocabulary. vSTM was a significant predictor of syntactic performance for both monolinguals and bilinguals, while vWM was a significant predictor of syntactic performance only for bilinguals. These findings suggest that impairments in vSTM, wVM and syntax are core clinical features in DLD, and that vWM makes a greater contribution to syntax in bilinguals than in monolinguals.