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27 Social pollinators such as honey bees face attacks from predators not only at the nest, but also during 28 foraging. Pollinating honey bees can therefore release alarm pheromones that deter conspecifics from visiting 29 dangerous inflorescences. However, the effect of alarm pheromone and its chemical components upon bee 30 avoidance of dangerous food sources remains unclear. We tested the responses of giant honey bee foragers, A. 31 dorsata, presented with alarm pheromone at a floral array. Foragers investigated the inflorescence with natural 32 alarm pheromone, but 3.3 fold more foragers preferred to land on the “safe” inflorescence without alarm 33 pheromone. Using GC-MS analysis, we identified eight chemical components in the alarm pheromone, of 34 which three components (1-octanol, decanal, and gamma-octanoic lactone) have not previously been reported 35 in this species. We bioassayed six major compounds and found that a synthetic mixture of these compounds 36 elicited behaviors statistically indistinguishable from responses to natural alarm pheromone. By testing each 37 compound separately, we show that gamma-octanoic lactone, isopentyl acetate, and (E)-2-decen-1-yl acetate 38 are active compounds that elicit significant alarm responses. Gamma-octanoic lactone elicited the strongest 39 response to a single compound and has not been previously reported in honey bee alarm pheromone. 40 Isopentyl acetate is widely found in the alarm pheromones of sympatric Asian honey bee species, and thus 41 alarmed A. dorsata foragers may produce information useful for conspecifics and heterospecifics, thereby 42 broadening the effects of alarm information on plant pollination. 43