[Objectives]  The honeybee (Apis mellifera ligustica) is an important pollinating insect which is inevitably exposed to various pesticides when pollinating crops. Fenpropathrin, a member of the pyrethroid family of insecticides, is widely used for pest control, however the effects of this insecticide on honeybee health have rarely been studied. We investigated the effects of sublethal doses of fenpropathrin on the survival, food consumption, expression of immune and detoxification related genes and the gut microbiota, of honeybees. [Methods]  The effects of sublethal doses of fenpropathrin on honeybee food (sugar solution) consumption and survival was assessed using the “oral-feeding tube” method. (2) Changes in the expression of detoxification and immune related genes, and in the gut microbiota, were measured 7 d after bees had been fed sublethal doses of fenpropathrin (1 mg/L and 5 mg/L). [Results]  Consumption of fenpropathrin significantly reduced the survival and food consumption of honeybees. Exposure to sublethal doses of fenpropathrin significantly inhibited Hymenoptaecin, Apidaecin and Cyp9q1 expression in honeybees, but up-regulated the expression of Defensin. The expression of Abaecin in the 5 mg/L treatment group was significantly higher than in the 1 mg/L treatment group. The effect of fenpropathrin on overall gut microbiota diversity was not significant, but it affected the gut microbiota distribution. [Conclusion]  Fenpropathrin can potentially affect the detoxification mechanism, immune system and gut microbiota, of honeybees. These results provide a basis for further exploring the complex molecular interactions between fenpropathrin and honeybees.