Rapid development of E-Learning applications brings large requirements of learning resources, especially web-based courseware. However, the high technical requirement of courseware developers and low reusability of learning resources heavily impede the process of courseware development. There is an urgent need for courseware authoring system to assist teachers who have no professional knowledge of computer technology to develop standard and reusable web-based coursewares. In this paper we presented such a tool named standard visual courseware authoring tool based content packaging specification. This authoring system has two major features. One is providing visual courseware organization, which achieves the aim that "What you see is what you get". The other one is standardization function based on content packaging specification for coursewares and inner learning resources. This authoring tool provides a standard way for web-based courseware development.