Natural polymer based food packaging has attracted more and more attention, but the lack of active functions of natural polymer hinders its application in the field of active packaging. In this study, chlorogenic acid carbon dots (CGA-CDs) was synthesized mildly using natural plant polyphenol CGA as carbon source, and CGA functionalized layered clays (LDHs@CGA) was introduced as reinforcing agent. Alg active films were fabricated by solution casting method using natural polysaccharide-alginate (Alg), CGA-CDs and LDHs@CGA. The results showed that the average particle size of the synthesized CGA-CDs was ∼2.0 nm, with obvious graphitized structure inside and active groups (-OH and -NH