A battery of nine auditory comprehension test, taken by seventy aphasics, was subjected to a factor analysis. Two factors, interpretable respectively as a lexical semantic and a syntactic comprehension factor, were obtained. Comprehension described in terms of these factors was found to be related to criterion variables of importance, namely the Token Test and a rating of comprehension in daily life. Broca's aphasics were found to be more impaired in syntactic than in lexical semantic comprehension; Wernicke patients tended to have low scores on both factors. The results of this study support the view of independent lexically based and syntactic processing in auditory comprehension which can be differentially disrupted by brain damage.