摘要：The main p.op.se of this research was to develop.a two-step.biodiesel p.oduction technique from animal fat as a raw material. The develop.d p.ocess consists ofesterification and transesterification step.. With sp.cial attention to op.imize the first step.is acid catalyzed esterification to reduce free fatty acid content and the second step.is alkali catalyzed transesterification for converting triglyceride to fatty acid methyl ester or biodiesel. Animal fat containing 78.80 mg KOH/g of high acid value and molecular weight of 851 g/mol with the highest oleic acid content was used as raw material. Resp.nd surface methodology （RSM） was ap.lied for the exp.riment design. This were 20 exp.riments involving the three investigated variables of methanol to animal fat ratio, amount of sulfuric acid catalyst and reaction time that were studied on esterification to op.imize the condition for decreasing acid value in animal fat less than 2 mg KOH/g. The animal fat with low acid value was further exp.rimented in transesterification step.to obtain fatty acid methyl ester or biodiesel. Animal fat biodiesel is further investigated by determining its fuel p.op.rties according to the ASTM standard test method.