Abstract:Both Cinnamomum septentrionale Hand. -Mazz. and Cinnamomum platyphyllum (Diels)Allen are endemic to China. The plant materials were collected from West Hubei In May-June, 1983. Both the essential oils, extracted from fresh leaves by steam distillation, were analysed in detail by means of capillary GC/MS/DS on Finnigan-4510 type. The result indicates that the major component of both essential oils s trans-methyl isoeugenol with the amount of 85.71% and 94.04% for C. septentrionale and C. platyphyllum respectively. The two species which are very rich in West Hubei are new important plant resources for transmethyl isoengenol.