Purpose - The purpose of this study is to review and analyze the status of word-of-mouth (WOM) research in the business-to-business (B2B) context and discuss and identify new possible future directions. Design/methodology/approach - A systematic review was conducted and 36 articles on B2B WOM were collected to evaluate the current state of the literature and clarify possible future research directions. Findings - This thematic analysis categorize these articles into three themes: WOM generation, WOM usage and reference marketing. Under each theme, the authors reveal research findings unique to B2B research and different from business-to-consumer (B2C) WOM research. This study identifies several research questions that should be addressed by future research. Originality/value - Both academic researchers and business practitioners recognize that WOM plays an essential role in B2B marketing. However, no review paper focuses on WOM in the B2B context. Findings in the B2C WOM literature suggest that WOM substantially influences firms' performance, but that managers cannot simply attempt to extrapolate B2C findings to the B2B arena. By synthesizing and assessing prior research on WOM in the B2B context, this study contributes to a better understanding of the B2B WOM phenomenon and facilitates future research on this topic.