Objective: To study the changes of volatile oil from different compatibility of Guizhi decoction and explore their connection.
Methods: The volatile oil of Cinnamomum cassia and different compatibility of Guizhi decoction extracted by steam distillation were analyzed by GC-MS.
Results: The main components of volatile oil in Cinnamomum cassia were found in different compatibility of Guizhi decoction and they accounted the most amount of total volatile oil,but the contents of the main components were decreased, there were more components existed in different compatibility of Guizhi decoction than those in Cinnamomum cassia, the new components came from Zingiber officinale mostly.
Conclusion: GC-MS can be used to reflect the changes of volatile oil from different compatibility of Guizhi decoction, and the result will provide some evidence for the research of regular pattern of compatibility in Guizhi decoction.