针对知识库在一致性方面存在的问题，给出了影响知识库一致性的循环、冲突和冗余的定义，并在将规则形式规范化的基础上，给出了规则等价比较的算法。根据该算法并结合产生式系统的特点，给出了判断规则循环、冲突和冗余的算法。最后，给出了在ｗｉｎｄｏｗｓ环境下，基于ＶｉｓｕａｌＣ＋＋的编程实现。这些算法及其实现方法可以帮助领域专家和知识工程师有效地维护知识库，并为进一步提高系统的性能奠定了基础。该方法已在电力通信网智能故障诊断知识库中获得应用，取得了良好的效果。 Aiming at the problems existing in consistency of knowledge base, this paper gives the definition of cycle, conflict and redundancy which affect the consistency of knowledge base. Based on the formalization of rules, an algorithm for the equivalence of rules is given. According to the algorithm and the characteristics of the production system, an algorithm for judging rules circulation, conflict and redundancy is given. Finally, given in the windows environment, based on VisualC + + programming. These algorithms and their implementation methods can help domain experts and knowledge engineers effectively maintain the knowledge base and lay a foundation for further improving system performance. The method has been applied in the intelligent fault diagnosis knowledge base of power communication network, and has achieved good results.