By combining the operators? experience and the sample data, this paper presented how to build the model of customer fraudulent with Bayesian network based on the data mining.

• 将电信业务人员的经验知识和样本数据相结合，在数据挖掘技术的基础上，提出了一种基于贝叶斯网络的电信话费欺诈建模方法。