The advent of Web 2.0 technology has afforded language educators more useful technology for English as a foreign language (EFL) teaching. This article reviewed 31 empirical studies investigating the employment of web-based technology to enhance EFL learners' speaking performance. The findings indicated that overall, web-based language learning (WBLL) could be classified into five major groups: general websites providing linguistic inputs, blogging platforms, communication tools, project-based learning tools and learning management systems. While the available linguistic input online, e.g. web articles and videos, helped to enhance learners' linguistic and background knowledge, other communication/chat tools facilitated peer interactions and collaborative learning. Audio- and video-based blogging provided convenient platforms for learners to practice their speaking through sharing their personal experiences. Moreover, Web 2.0 technology as a learning management system helped to create a ubiquitous learning environment, where L2 learners could engage in the language learning process without time and space constraints. WBLL was also found to reduce L2 learners' learning anxiety while making them become more active, motivated language learners. In addition, the role of language instructor in web-based technology implementation was also found to be crucial, e.g. monitoring L2 learners' learning progress and providing feedback. Further research, however, is warranted to address existing methodological drawbacks of previous studies by recruiting larger sample size, conducting long-term research and controlling for confounding factors, e.g. prior L2 speaking ability and technology usage experience.