Abstract: Through discussing the evaluation methods of subjective trust in open network，a new approach of subjective trust evaluation based on credibility theory is presented with considerations of the fuzzy nature of the subjective trust.And then under the situations that the key attributes of subjects are characterized as fuzzy variables，a simulation technique is given to calculate the credibility of the subjective trust.The example indicates that the presented approach is feasible and effectual for valuing the subjective trust in open network.

Key words: trust management, subjective trust, trust class, credibility measure, fuzzy variable

摘要： 通过对开放网络环境中主观信任评价方法的讨论，考虑到主观信任的模糊性，提出以可信性理论为基础的主观信任量化表述与评价方法，并给出了主体信任属性评价值为模糊变量情形下主观信任可信性的模拟计算方法。实例分析表明，该方法对主观信任评价是可行和有效的。

关键词: 信任管理, 主观信任, 信任类型, 可信性测度, 模糊变量