Objectives:We investigated aircraft noise related stress by heart rate variability(HRV). Methods:To evaluate chronic effects of noise exposure on stress,we studied 554 subjects(58짹15yr) who have lived more than 10 years within 5 km of airport as exposed(E) and 213 subjects(56짹16 yr) as control group(C).5min HRV was analyzed.To evaluate acute effect of aircraft noise exposure,24hr HRV from 24hr Holter was analyzed and compared with simultaneously measured 24hr aircraft noise in 55subjects(54짹10yr,28 men) as exposed(E24) and 19subjects(55짹8yr,11men) as control(C24). Results:5min mean heart rate(HR) was higher in E than C(62.6짹0.5vs60.8짹0.6bpm,p=.017),However there was no significant difference in 5min SDNN and LF/HF between E and C(p>.05).Age,sex,body mass index and SBP adjusted HR was not different(E:62.5짹0.4vsC:60.8짹0.7 bpm,p=.058).Men of E showed higher adjusted HR than that of C(61.9짹0.7vs.59.2짹0.9 bpm,p=.035).Log(SDNN) of 24hr was not different(E24:4.90짹0.04vsC24:4.89짹0.07,p=.889,age and sex adjusted).Log(LF/HF) of 24hr was also not different(E24:0.84짹0.08vsC24:0.85짹0.14,p=.947,age and sex adjusted).Analysis of LF/HF with LAeq and Lmax every 5 minutes,showed 34% increase of LF/HF per 10 dB(A) increase of LAeq,and 22% increase of LF/HF per 10dB(A) of Lmax. Conclusions:Chronic exposure to aircraft noise may increase heart rate in men,but has no effect on HRV.However simultaneously acute increase of LF/HF with elevation of aircraft noise indicates that aircraft noise may induce stress acutely.