Abstract:Tea，as one of China's specialties，is the most popular beverage for all over the world.Especially in China，tea has a deep audience and relatively mature industrial chain and processing technology.China has a very long history of growing and making tea.According to the different degrees of fermentation，tea can be divided into four categories：non-fermentation，mild fermentation，semi-fermentation and whole fermentation.In this paper，the key technologies of different kinds of tea in the process of processing were introduced，and the chemical changes of different kinds of tea in the process of making tea were compared.By comparing and analyzing the effects of chemical changes on the quality of tea （color，aroma，taste，phyllotaxis）in the process of making different kinds of tea，it was clearly pointed out that the six kinds of tea had better processing technology，so that tea growers could get better improvement in tea cultivation and tea processing.It played an important role in improving the physical and chemical quality of tea and enriching the types of tea products.