Multimedia, especially video, is widely used in educational applications. More and more universities and corporations now provide videotaped lectures online for knowledge sharing and learning. However, people often have difficulties in finding specific information in these lecture videos because of the unstructured and linear nature of video. Segmenting the videos into short clips based on topic transition and organizing these video segments into well-formed browsing structures will facilitate information searching and may further enhance learning. In this paper, we present the design and implementation of a Web-based multimedia learning system with automatically generated browsing structures such as hierarchical tables of contents, index and hyperlink. A pilot study was conducted to evaluate the effectiveness of the system in supporting learning.