Theories of agrammatism have been challenged by the discovery that agrammatic patients can make above-chance judgements of grammaticality. Chinese poses an interesting test of this phenomenon, because its grammar is so austere, with few obligatory features. An on-line grammaticality judgement task was conducted with normal and aphasic speakers of Chinese, using the small set of constructions that do permit judgements of grammaticality in this language. Broca's and Wernicke's aphasics showed similar patterns, with above-chance discrimination between grammatical and ungrammatical forms, suggesting once again that Broca's aphasics are not unique in the degree of sparing or impairment that they show in receptive grammar. However, even for young normals, false-negative rates were high. We conclude that there is some sensitivity to grammatical well-formedness in Chinese aphasics, but the effect is fragile for aphasics and probabilistic for normals, reflecting the peculiar status of grammaticality in this language.