The domestic anion exchange resin 315 was selected to separate lactic acid from the fermentation broth. Adsorption isotherm, kinetics, effect of dynamic adsorption and elution on lactic acid, acetic acid, pyruvic acid and citric acid were studied. Adsorption isotherm results showed that the Freundlich isotherm equation agreed well with the adsorption data of organic acids on anion exchange resin 315, and the characteristic parameter of this equation n>1. It displayed that the adsorption process belonged to favorable adsorption. Besides, the adsorption kinetics of organic acids on anion exchange resin 315 was mainly controlled by liquid film diffusion, and it accorded well with the Boyd liquid film diffusion model. The optimum dynamic adsorption and elution conditions were determined: adsorption flowrate, 15 BV／h; pH 188; eluent, deionized water; elution flowrate, 1 BV／h. Under these conditions, the lactic could be well separated from the fermentation broth to achieve the purpose of increasing the yield of lactic acid products and improving product purity.