Background: In many languages a weakness in non-word repetition serves as a useful clinical marker of specific language impairment (SLI) in children. However, recent work in Italian has shown that the repetition of real words may also have clinical utility. For young typically developing Italian children, real word repetition is more predictive of particular grammatical abilities than is non-word repetition. This finding is important because these particular grammatical abilities--the production of present-tense third-person plural inflections and direct-object clitic pronouns--are precisely those that are problematic for Italian-speaking children with SLI. Along with their grammatical requirements, these two morpheme types present a significant phonological/prosodic challenge for these children. Aims: To replicate the findings with young typically developing Italian children and to determine whether real word repetition is also more predictive of the use of these two morpheme types than is non-word repetition in a group of Italian-speaking children with SLI. Methods & Procedures: Seventeen Italian-speaking children with SLI and 17 younger typically developing children matched for mean length of utterance participated in tasks of real word and non-word repetition as well as tasks requiring the production of direct-object clitic pronouns and present-tense third-person plural inflections. Outcomes & Results: Children with SLI were less accurate than their younger peers on all measures. Importantly, for the younger typically developing children, real word repetition explained a significant amount of variance in the use of third-person plural inflections and direct-object clitic pronouns. For the children with SLI, in contrast, non-word repetition was a significant predictor, whereas real word repetition was not a contributing factor. Conclusions & Implications: It is argued that in Italian SLI, the grammatical details showing the greatest weakness present phonological/prosodic obstacles as well as grammatical challenges to these children. Consequently, non-word repetition emerges as a predictor of these grammatical weaknesses in SLI, unlike the profile observed in typically developing Italian children.