To establish a gas chromatography-mass spectrometry(GC-MS)combined analysis method to identify the chemical constituents of Volatile Oil of Cinnamomum Camphora(VOCC)，and to explore the effects of VOCC on the common carotid artery in rats.Methods:The method of our study were as follows:extracted by steam distillation，dehydrated in anhydrous sodium sulfate dehydrated in -4 ℃ refrigerator，analyzed the composition of VOCC by GC-MS，combined with computer search to analyze and identify the separated compounds.The relative content of each component was calculated by one-step method; the rat common carotid artery vascular ring was made into endothelium-free and endothelium-containing specimens，and phenylephrine(PE)was used as a vasoconstrictor to observe VOCC on role of ring pre-contraction on isolated rat blood vessels.Results:A total of 45 chemical components were isolated，and 40 compounds identified were with a similarity above 90%，accounting for 99.86% of the total VOCC.Natural borneol had the highest relative content，accounting for 93.49% of the total VOCC; VOCC could inhibit PE common carotid artery contracted without endothelium dependence，and the vasodilator effect of VOCC on the common arterial artery was obviously dose-dependent.Conclusion:Under this experimental condition，natural borneol is separated from the baseline.This method can be used for quantitative analysis of natural borneol raw materials and preparations.VOCC has a significant antagonistic effects on PE-induced vasoconstriction，suggesting that it has a good vasodilator effects.