Addressing to improve the trustworthiness of Business Process Re-engineering (BPR) system, this paper proposes a trustworthy construction approach to solve the problem mentioned above. Firstly, we analyze related literatures about the topic, we realize that main reason causing to reduce trustworthiness of BPR system is due to break of trustworthy connectivity between front configuration tools and business processes operating server. Secondly, as the primary methods composing of the construction approach, a semantic verification method is illustrated in detail based on Petri net. Finally, a case study is introduced to explain how to use the above construction approach of BPR system.