Abstract：In order to identify the essential oils ingredients in oil cells at room temperature, utmost avoid the change of essential oil active ingredients and avoid sample pretreatment and extractions which can be labor intensiveThe oil cell of Hedychium villosum Wall in situ was analyzed by means of Raman spectroscopyFresh samples were prepared by freehand sectionUnder the DXR Laser conforcal micro Raman spectrometer, the oil cells can be seen with objective lens of 10×The sample has similar Raman spectrum with cineolThe Hedychium villosum Wall and cineol high intensity bands are present at 2 928/2 921, 647/652 cm1，middle intensity bands are present at 540/545, 808/813, 915/920, 926/930, 1 012/1 016, 1 075/1 080, 1 270/1 273, 1 427/1 432 cm1Its indicates that principal component of sample is cineolThe 25 presented spectroscopic bands of Hedychium villosum Wall oil cell correlate very well with cineol
