The correlation between stages of vibration disease and hypesthesia of temperature sense detected with our thermo-esthesiometer was analyzed. We measured the warm and cool thresholds among operators (644 males) in three occupational categories with vibration exposure from hand-held vibratory tools, such as grinder, drill, sander, impact-wrench, bush-cutter and chain-saw. Through the examination of the relationship between the temperature threshold and the stage of vibration disease, the following was revealed: The warm sense threshold elevated parallel with the aggravation of vibration disease, although the skin temperature had no change or reduction. The hypesthesia of the cool sense threshold appeared in serious cases of vibration disease. This abnormality of the cool sense indicated a more intensive disorder than that detected by the warm sense abnormality. The width of the neutral zone between the warm and cool thresholds of the intact subjects was 6.6 degrees C +/- 3.8 C degrees. This neutral zone was enlarged with the aggravation of the vibration disease. Data also showed that the measurements of temperature sense threshold should be carried out under standardized room temperature.