An epidemiological study on the prevalence rate of systemic reactions among forestry workers exposed to hymenoptera stings was performed. A sample of 100 Forestry Department Agents was studied using a questionnaire with the purpose of evaluating the prevalence rate of systemic reactions due to hymenoptera stings. From the questionnaire it was found that 78 (78.0%) of the subjects had histories of Hymenoptera stings and 5.0% had experienced systemic reactions. In conclusion, we found that the percentage of systemic reactions was relatively higher than that in the general population previously reported (0.3-3.3%). Efforts should be made for the sake of these Hymenoptera hypersensitive workers to popularize venom immunotherapy.