Zinc is an essential element for animals, while zinc salt cannot be absorbed effectively. In this work, a sustained release vanillin-chitosan Schiff base (VCSB) zinc complex additives (VCSB-Zn2+) was prepared and a new in vitro sustained release system suited for this complex was effectively constructed. The structure of VCSB and VCSB-Zn2+ were characterized by FT-IR, 1H NMR, TGA, XPS and SEM. VCSB exhibited a more rapid End-point and higher capacity of chelating Zn2+ than chitosan, and it was also closely related to the content of -C=N. Furthermore, VCSB-Zn2+ showed excellent sustained release ability at simulated gastric fluid (SGF) because of the acid slow-dissolving ability. And the L-cysteine at simulated intestinal fluid (SIF) absorbed Zn2+. Additionally, the sustained release curves followed first-order and Korsmeyer-Peppas models, which described Zn2+ sustained release cause by the dissolution of VCSB-Zn2+ and Fick diffusion. Therefore, VCSB-Zn2+ is facilitating the application and promotion of zinc additives.