Abstract. A common task in business process modelling is the verification of process models regarding syntactical and structural errors. While the former might be checked with low efforts, the latter usually requires a complex state-space analysis to prove properties like deadlock-freedom of the models. In this paper, we address the issue of deadlock detection with a novel approach based on business process querying. Using queries, we are able to detect a broad range of common structural errors that lead to deadlocks, such as misaligned splits and joins. While not being complete, the proposed approach has the advantages of low computational efforts as well as providing graphical outputs that directly lead to the errors.