Abstract: A kind of self-assembled tea polyphenol(TP), gelatin(Gel)and chitosan(Cs)nanoparticles(TP-Gel-Cs)was prepared and evaluated in vitro. TP-Gel-Cs nanoparticles were fabricated based on an electrostatic bonding between Gel and Cs, together with a non-covalent interaction between TP and polysaccharide modified Gel. The optimal formulation of nanoparticles was a mass ratio of 1. 5 ∶3 ∶1 for TP-Gel-Cs nanoparticles. The present experiments showed that the primary interaction exiting within the TP-Gel-Cs matrix was non-covalent bond. The mean diameter of the particles was 971. 50 nm with a polydispersity index of 0. 22, the Zeta-potential was -10. 44 mV at the neutral condition and +33. 23 mV at pH 5. 4. The entrapment efficiency and loading capacity of the particles were 90. 42% and 26. 82%, respectively. The stability of TP at 25 ℃ was significantly improved by formation of TP-Gel-Cs nanoparticles, the nanoparticles exhibit both pH-sensitive and controlled release properties. Taken together, the preparation process is simple, mild and green, which may be a promising method to encapsulation polyphenol substances.