Abstract: Flavonoids are secondary metabolites of plants, which have a variety of important biological functions and have potential beneficial effects on human health. As antibacterial agents, flavonoids play an important role in the interaction and defense reaction between plants and microorganisms. This article summarizes the biosynthetic pathways and regulation rules of flavonoids, focusing on the effects of external environment such as light, temperature, moisture, radiation, hormones, minerals and transcription factors such as MYB, bHLH, WD40 and NAC on the synthesis of flavonoids. Strengthen research in this area, aiming to provide guidance for the better development and utilization of plant flavonoid functional ingredients.