Based on learning theories and Web technologies, a Web-based CALL system for Chinese Tang poetry is developed in this study. The system mainly consists of four modules: an information management subsystem, a Tang poetry learning subsystem, an online examination subsystem and a communication subsystem. This system helps learners 1) browse the Tang poetry learning resources, 2) evaluate knowledge levels of Tang poetry online, 3) highlight and comment on Web pages using an online annotation tool, and 4) communicate with other learners and teacher using communication tools such as BBS, chat-room and e-mail. The functions described above provide an environment for enhancing the interaction between learner and Web teaching materials, and for increasing discussions between learners and teachers, and between learners and learners.