The 2009 International Conference on Web Information Systems and Mining (WISM 2009) was held in Shanghai, China 7–8 November 2009. WISM 2009 received 598 submissions from 20 countries and regions. After rigorous reviews, 61 high-quality papers were selected for publication in this volume. The acceptance rate was 10.2%. The aim of WISM 2009 was to bring together researchers working in many diff- ent areas of Web information systems and Web mining to foster exchange of new ideas and promote international collaborations. In addition to the large number of submitted papers and invited sessions, there were several internationally well-known keynote speeches. On behalf of the Organizing Committee, we thank the Shanghai University of El- tric Power for its sponsorship and logistics support. We also thank the members of the Organizing Committee and the Program Committee for their hard work. We are very grateful to the keynote speakers, invited session organizers, session chairs, reviewers, and student helpers. Last but not least, we thank all the authors and participants for their great contributions that made this conference possible. November 2009 Wenyin Liu Xiangfeng Luo Fu Lee Wang Jingsheng Lei Organization Organizing Committee General Co-chairs Jialin Cao Shanghai University of Electric Power, China Jingsheng Lei Hainan University, China Program Committee Co-chairs Wenyin Liu City University of Hong Kong, Hong Kong Xiangfeng Luo Shanghai University, China Local Arrangements Chair Hao Zhang Shanghai University of Electric Power, China