輪班作業醫護人員工作壓力及心智疲勞情況往往比一般作業人員為高，為了紓解壓力及消除疲勞，精油為常使用於各種紓壓、解勞的產品，但缺乏科學驗證，功效無法獲得證實。本研究目的為使用客觀的腦波及心率變異度測定等生理量測技術，以評估精油吸入對消除輪班作業人員心智疲勞之功效。從腦波量測數據所反映困倦水準和放鬆水準，及心率變異度變化所反映之心智負荷狀態，來評估輪班作業醫護人員使用精油對消除心智疲勞之實質功效。徵求南部某醫院輪班作業醫護人員進行實驗測試，受測對象計51人。實驗分為四階段即工作前、工作後、嗅聞精油中、嗅聞精油後，於各階段填寫室內(辦公室)作業自覺疲勞評估量表及量測10分鐘腦波和心率變異度。測試結果發現日班於嗅聞精油在覺醒水準θ/α及困倦水準(θ+α)/β皆有顯著變化，顯示日班於嗅聞精油對於消除疲勞的效果優於夜班。心率變異度測試結果發現沒有統計上的顯著水準，這可能表示受測者心率變異度的個別差異太大導致量測的結果統計上無顯著差異，較不適合做為評估的指標。由個人主觀上室內(辦公室)作業自覺疲勞評估量表，顯示日班嗅聞精油後消除疲勞之自我感覺較夜班為佳。綜合上述實驗量測結果，本研究發現嗅聞精油對日班消除疲勞之效果較夜班為佳。 Shift worker’s stress and mental fatigue is often higher than the non-shift worker. In order to relieve stress and fatigue, a variety of essential oils are often used by shift workers. Owing to lack of objective measured data of the effect on dispelling fatigue for essential oil, the reliability of subjective experiment from questionnaire has always been challenged. The purpose of this study is to evaluate shift workers the effect on dispelling mental fatigue for inhaling essential oil by using physiological indices including electroencephalography (EEG) and heart rate variability (HRV). The basic and ratio indices of EEG power reflecting the drowsiness and relaxation levels, and the variety of HRV reflecting the condition of mental workload were used to evaluate the effect on decreasing mental fatigue substantially for shift workers inhaling essential oils. Fifty-one shift workers recruited for subjects participated as volunteer subjects from a hospital in southern Taiwan. The experiment was divided into four stages before work, after work, inhaling essential oils, after inhaling essential oils, at each stage (office) job subjective fatigue rating scale and 10 minutes EEG and heart rate variability (HRV) were measured. Test results showed that day shift-worker inhaling essential oils had remarkable increased in the θ/α and (θ+α)/β, inhaling essential oils. For the day shift-workers, the effect on decreasing fatigue was better than that for the night shift-workers. HRV test results showed no statistically significant level, which may indicate that individual differences in the subject's HRV is too great. By individuals subjectively indoor (office) job subjective fatigue assessment scale, shows that the essential oil for day shift-worker decreasing fatigue after inhaling oils feel better than the night shift-worker. The study finds that the effect on decreasing fatigue for essential oils on day shift-worker is better than that on night shift-worker.