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Language disorders can be the first and most prominent symptom of certain neurodegenerative diseases. Determining whether they come from impairments in language production or a deficit in receptive language due to lexicosemantic difficulties can help characterize the clinical phenotype between progressive non-fluent aphasia (PNFA) and semantic dementia (SD). The aim of this study is to determine whether the Repeat and Point Test (RPT) can reliably differentiate between the language disorders of PNFA and SD. Participants were required to repeat 25 multi-syllabic concrete nouns, then to point to the corresponding pictures among six semantically or perceptually similar distractors. The performances of three patients with PNFA and 11 patients with SD were compared to those of 50 healthy controls using statistical methods based on single-case studies. A double dissociation was identified: PNFA patients had impairment in the repetition component of RPT, while their performance in the pointing component were no different to healthy controls. The performance of SD patients was the opposite, confirming a perfect classification of these two linguistic profiles. The RPT is of undeniable clinical interest in order to quickly and accurately discriminate between the linguistic profiles of PNFA and SD patients. The RPT provides suitable information to guide an in-depth cognitive examination in order to understand the origins of these language disorders.