Plenty of volatile compounds with different structures existed in natural products, which could objectively reflect the flavor characteristics of natural products. This paper reviewed the research progress of aroma forming mechanism, characteristic aroma formation theory and the synergistic method of aroma. The olfactory receptor combines with the aroma molecules to activate and transmit to the cerebral cortex then the body perceives the aroma. The molecular vibration theory and recognition theory were expounded to explain the possible causes of characteristic aroma formation. The methods of synergistic effect of aromatic compounds in natural products were clarified from the microscopic perspectives of threshold, S-curve, OAV, and σ-τ method, and the macroscopic of calcium ion imaging method and cell electrophy-siology. The existing problems have been summarized and the future research is prospected.