In this paper, we propose a preliminary approach for automating web service verification. We use Semantic Markup for Web Services (OWL-S) to describe web service behavior. We parse the OWL-S file and transform it automatically to a corresponding Markov chain diagram or Markov decision process, which are then transformed to a PRISM model to be used as input by PRISM, a probabilistic model checker, to verify automatically the web service behavior. We provide an implementation of the transformation algorithm through a developed software tool automating all the transformation and verification activities.