Anaerobic digestion of piggery waste generates effluents which containing high concentration of inorganic nitrogen and phosphorus can result in eutrophication of natural water bodies when discharged without adequate treatment. Microalgae can be cultured in effluent derived from the anaerobic digestion of piggery waste for nutrient removal and biodiesel feedstock production. In this study, the piggery wastewater was used as a nutrient source for culturing the green microalgae, Chlorella sp B5. The effect of dilution of the effluent on the nutrient removal efficiency of Chlorella sp.B5 was determined. During an eight day batch culture, Chlorella sp.B5 grew fastest in an diluted effluent with a initial COD concentration of about 300400 mgfL. The maximum specific growth rate and biomass concentration of Chlorella sp. 85 were 0.306/day and 0.19 g/L, respectively. The culturing system of Chlorella sp. B5 removed ammonia, total phosphorus and COD of piggery wastewater by 60 - 95.8 percent, 22 - 68 percent and 34 - 73.8 percent, respectively. The lipid content of algal biomass after 8 days were 28-30 percent of dry weight.