Abstract：This study makes a comparative analysis of the in vitro anti-oxidative effect of vitamin C(VitC) and VitC phosphate complex (VitC-PC). Mice peritoneal macrophages were prepared and incubated in vitro. Lipopolysaccharide (LPS) of Salmonella was used to induce the oxidative stress. The cells were treated by VitC and VitC-PC of different concentrations, respectively. Extracellular nitric oxide (NO), lactic dehydrogenase (LDH) and malonaldehyde (MDA) and intraocular inducible nitric oxide synthetase (iNOS) were determined to characterize the extent of inflammatory response, the membrane integrity and the lipid peroxidation, respectively. Untreated macrophages were also incubated with VitC or VitC-PC of different concentrations, and the intraocular VitC was measured to estimate the incorporation efficiency of VitC. The results show that the macrophage uptake of VitC-PC is more significant than that of VitC in a high concentration (P<0.05). VitC-PC would inhibit LPS induced macrophage release of NO, and the lipid peroxidation occurs (to generate MDA) and the cell membrane damages (to release LDH), which is more significant than VitC (P<0.05). It is concluded that it is easier for VitC-PC than for VitC to enter into cells and to prevent the damage of high molecules by over production of free radicals.