We investigate the usefulness of syntactic knowledge in estimating the quality of English-French translations. We find that dependency and constituency tree kernels perform well but the error rate can be further reduced when these are combined with hand-crafted syntactic features. Both types of syntactic features provide information which is complementary to tried-and-tested nonsyntactic features. We then compare source and target syntax and find that the use of parse trees of machine translated sentences does not affect the performance of quality estimation nor does the intrinsic accuracy of the parser itself. However, the relatively flat structure of the French Treebank does appear to have an adverse effect, and this is significantly improved by simple transformations of the French trees. Finally, we provide further evidence of the usefulness of these transformations by applying them in a separate task ‐ parser accuracy prediction.