(1) It is an aliphatic ether of the cedrol.

(2) The major chemical component of the oil was cedrol.

(3) The factors affecting the SPME efficiency of cedrol such as fiber type, equilibrium time, extraction temperature, stirring speed and ion strength of medium were exa-mined and optimized.

(4) A method for the determination of cedrol in seawater was developed by gas chromatography-mass spectrometry coupled with solid - phase microextration(SPME).

(5) In this paper, the cedrol methyl ether was synthesized by sodamide method.

(6) A certain reference value was indicated in this experiment for industry synthesis of cedrol methyl ether by sodamide method.

(7) The fir essential oil was extracted from fir root by steam distillation method, from which cedrol was extracted, and then, cedrol methyl ether was synthesized based on cedrol.