21世纪是信息时代，信息在社会经济中的战略地位日益显现。作为传递信息的载体，信息系统充当着举足轻重的角色，利用好信息系统已成为企业决胜未来的主要因素之一。自改革开放以来，我国企业经过较长时间的高速发展，不同程度上已经建立了各自的信息系统，但信息系统的应用效果如何，应该怎样评价，一直是学术界和企业界普遍关心的热点话题。 本文对信息系统评价领域的相关文献进行了详细阐述，分析了现有系统评价的不足及指标体系设置上存在的一些问题，借鉴已有的关于有效性的研究提出了企业信息系统有效性的概念，并对有效性的度量标准进行了三维度分析。在此基础上，针对存在的问题，结合指标体系的构建方法，提出了一套基于技术、经济和管理维度的企业信息系统有效性评价指标体系，构建了企业信息系统有效性评价模型。最后，运用该模型，对西安西电高压电瓷有限责任公司信息系统的有效性进行了评价。根据评价结果，指出了该系统有效性可进一步提高的建议。本文选择了层次分析法作为确定指标权重的主要方法，选取模糊评价法进行了评价。

Entering 21st century, the human society is striding forward into the information times. Information becomes more and more important in society and economy life. As a carrier to transmit information, information system plays a decisive role. It has become one of the main factors to win in the future for the business to make good use of information system. Since the reform and opening policy, Chinese enterprises have developed for a long time, and built their own information systems in varying degree. However, how about is the application effectiveness of information system and how to evaluate it, has always been a hot topic of common concern in academe and business circles. In this paper, the literatures in the field of information system evaluation are elaborated, the deficiency about existing system evaluation and a number of issues on index system settings are analyzed. Drawing on existing research, this paper brings forward the concept of validity of the enterprise information system, and expounds the standards of measuring validity based on three deminsions. On this basis, for the existing problems, with the index system construction methods, this paper puts forward a set of index system based on techonlogy deminsion, economy deminsion and management deminsion, and constructs the evaluation model of enterprise information system validity. Finally, this paper evaluates the validity of information system of XI’AN HING-VOLTAGE ELECTRICAL PORCELAIN FACTORY . Based on the evaluation results, this paper makes proposals that the system can be further improved. This paper choose AHP as the primary means of weight, and select the Fuzzy Evaluation as the means of evaluation.