Since the industrial revolution, the atmospheric carbon dioxide (CO₂) concentration has increased by approximately 40%, mainly due to anthropogenic activities (e.g., burning of fossil fuel). Approximately one third of CO₂ released into the atmosphere is eventually absorbed by ocean, lowering the pH of surface seawater and causing wholesale shifts in seawater carbonate chemistry, a phenomenon known as "ocean acidification" (OA). During the past 250 years, the average surface seawater pH has decreased by approximately 0.1 units, from 8.21 to 8.10. According to the prediction of Intergovernmental Panel on Climate Change (IPCC), the average surface seawater pH will decline to 7.7-7.8 by the end of the 21^st century and 7.3-7.4 around 2300. Behavior, the first response exhibited by fish to stimulus, plays important roles in fish reproduction, predation, and anti-predation. Therefore, effects of OA on marine fish behavior has, recently, garnered considerable attention and gradually become a new research hotspot. Although not immediately lethal, OA has been demonstrated to adversely influence marine fish behavior, especially their predation, anti-predation, behavioral lateralization, shoaling behavior, and habitat detection and seeking behavior, by disrupting sensory system, interfering with GABA_A-receptor function, and hindering cell signal transduction. Behavior normality is likely to impair fitness and population survival, which will in turn affect species interactions and ecological processes, and subsequently pose a great threat to ecosystem structure and functioning. However, current knowledge on marine fish behavior modification is mostly obtained by laboratory simulation and restricted to single species, life stage, leading to an incomplete view of how OA and other coinciding environmental stressors can affect the ecological interactions that structure biological communities. More importantly, China has a long coastline, vast sea area, abundant fish resources, and developed fishing and aquaculture industry; however, only few studies in China have focused on fish behavior alteration under near future OA scenarios. These, undoubtedly, limit our ability to precisely forecast the potential risk of ecosystem in a rapidly changing marine environment, and deal with OA. We therefore reviewed published literature on marine fish behavior under OA conditions, synthesized current understanding and identified knowledge gaps of how OA might affect marine fish behavior, assessed the potential ecological risk, and discussed the underlying mechanisms. Finally, key suggestions have been provided to facilitate future studies, especially those in China.