Abstract: Objective The present study was conducted to get an insight into the incidence rate of hypertension of the railway workers under high-temperature circumstances and provide a scien- tific basis for the prevention of the disease．Methods 9568 railway workers working under high-temperature circumstances in Jiangxi were selected by stratified sampling and surveyed thmugh questionnaire investigmion and measurement of blood pressure．Results Of the 9568 workers，370 eases were found to suffer from hypertension．The incidence being 3.87％ and the age 42.58 years The prevalence rate of isolated hypertension was 0.89％ and the age was 39.36 years Statistically there was a significant difference in the average age of onset of hypertension between the workers working in the open air under high—temperature circumstances and those under the same high tem-perature but indoors．With the average age of onset of the disease 1.45 years earlier in the workers working in the open air than those indoors(u=2.17．P<0.05)．Conclusion The prevalence rate of hypertension among railway workers under high-temperature circumstances is lower than that of others in the same age group in our country．It is seen that working in the open air under-high temperature circumstances has a negative influence on the workers，leading to hypertension occur-ring at an earlier age．