Abstract: Plant polyphenols have a wide range of pharmacological activities and application prospects. Liquid polyphenol preparations have special physical phases and complex chemical compositions, with problems such as poor stability and easy precipitation during production and marketing. Taking the multi-precipitation mechanism of plant polyphenol liquid preparations as an example,we discuss the chemistry and composition of the precipitation, how it forms, whether precipitationcan be controlled, and the interaction law of three precipitation approaches. An unstable mechanism model is proposed where hydrolyzed tannin hydrolysis and catechin non-enzymatic oxidative polymerization repeatedly induces associative colloid aggregation and precipitation. This study explains the complex physicochemical changes in polyphenol solutions and the microcosmic mechanism of instability in the induced system and proposes a steady state reconstruction of liquid polyphenol preparation consistent with the common law of precipitation and control. It has scientific significance for promoting the development and manufacture of high quality liquid polyphenol preparations.