In this paper we introduce fuzzy causal network as a qualitative model for service oriented computing. Firstly, we give a brief description of fuzzy causal network. Secondly, we explain how fuzzy causal network can be used as a qualitative model for service oriented computing. Thirdly, We use fuzzy causal network to model a real world problem in the area of service oriented computing to demonstrate the correctness and effectiveness of this model. Finally, we outline some open research problems for further study. The proposed model has potential to become a good framework for causal discovery and decision support in service oriented computing, especially in the cases where intensive interaction among various services are involved.