本文在证据理论与图模型研究的基础上,针对不确定性与关联性相结合的系统建模问题,提出并建立了证据网络模型,定义了证据网络的参数,总结了证据网络的建模特点;分析了证据网络模型的推理问题,建立了其推理策略和推理过程,推导出其正向推理算法和反向推理算法,并通过示例进行了计算验证;证据网络模型将为管理决策分析、系统工程管理等领域的问题分析和求解提供一种有效的技术方法支持. Based on the research of evidence theory and graph model, aiming at the problem of system modeling combining uncertainty and relevance, this paper proposes and establishes evidence network model, defines the parameters of evidence network, summarizes the modeling features of evidence network ; Analyze the reasoning problem of evidence network model, set up its reasoning strategy and reasoning process, deduce its forward reasoning algorithm and reverse reasoning algorithm, and verify the example through examples. The evidence network model will be used for management decision analysis, system Engineering management and other areas of problem analysis and solution to provide an effective technical support.