The aim of this article is to illustrate the use of the Bilingual Aphasia Test (BAT) with a Cantonese-Putonghua speaker. We describe G, who is a relatively young Chinese bilingual speaker with aphasia. G's communication abilities in his L2, Putonghua, were impaired following brain damage. This impairment caused specific difficulties in communication with his wife, a native Putonghua speaker, and was thus a priority for investigation. Given a paucity of standardised tests of aphasia in Putonghua, our goal was to use the BAT to assess G's impairments in his L2. Results showed that G's performance on the BAT subtests measuring word and sentence comprehension and production was impaired. His pattern of performance on the BAT allowed us to generate hypotheses about his higher-level language impairments in Putonghua, which were subsequently found to be impaired. We argue that the BAT is able to capture the primary language impairments in Chinese-speaking patients with aphasia when Putonghua is the second language. We also suggest some modifications to the BAT for testing Chinese-speaking patients with bilingual aphasia.