针对目前云环境下企业IT投资决策方面关于评价指标的不确定以及定量分析被忽视的问题,提出影响企业各业务信息系统进行投资决策的五个指标,并引入熵权TOPSIS评价方法对三种IT投资决策方案进行评价.最后以一个企业的IT投资决策为例,利用熵权TOPSIS法选出云环境下最适合企业信息系统进行投资决策的部署方案. Aiming at the problems of uncertain evaluation and quantitative analysis neglected in the IT investment decision-making of enterprises in the cloud environment at present, five indicators that affect the various business information systems of enterprises to make investment decisions are put forward. The entropy-weighted TOPSIS evaluation method is introduced to evaluate three IT Investment decision-making scheme.Finally, taking an enterprise’s IT investment decision-making as an example, using entropy TOPSIS method to select the most suitable deployment of enterprise information system investment decision-making in the cloud environment.