Perfluorooctane sulfonate (PFOS) is a synthetic chemical substance that has become a ubiquitous environmental contaminant. It has been used in both industrial and consumer applications for over 50 yr, resulting in high levels of contamination worldwide. The potential ecotoxicity of PFOS has recently become a focus of interest and concern. The aim of this study was to investigate the impact of PFOS on risk recognition and escape performance of juvenile qingbo Spinibarbus sinensis. Fish were exposed to a range of PFOS concentrations (0, 0.32, 0.8, 2 and 5 mg l −1 ) at different temperatures (18 and 28°C) for 4 wk, at which point their antipredator behavior and fast-start swimming performance were assessed. We found that PFOS exposure caused qingbo to increase the time they spent in the 'risky area' (the area of the experimental aquarium closest to the predator tank) and reduce their average distance from the predator, as well as resulting in a noticeable increase in latency time and a significant decline in maximum linear velocity, maximum linear acceleration and escape distance. Many of these effects were more pronounced at the higher temperature. Our results indicate that exposure to PFOS could have deleterious effects on survival-related behavior in fish.