These phenolic compounds have remarkable biological effects such as antibacterial, antiviral, antioxidant, anti-inflammatory, anti-cancer, hepatoprotective, antiendotoxin, anti-allergic, anti-diabetic, cardioprotective, anti-allergic activities, etc. In particular, chlorogenic acid, a prominent component with significant biological activities, is utilized as a marker compound to evaluate the quality of Flos Lonicerae in the Vietnamese and Chinese Pharmacopoeia.