Abstract: The technology of preparing biodiesel oil from lapeseed oil was studied. By GC and chemical analysis, the optimum technological conditions were obtained. Through cost accounting, the economic feasibility of the synthesis route from lapeseed oil was discussed. The combustion properties of biodiesel oil from lapeseed oils were also analyzed. Results showed that this biodiesel oil has cetane number of 52.8 and sulfur content of 0.003 8%, and the main technical specifications could reach or exceed the Germany biodiesel oil standard DIN-V51606, and possessing widespread application prospect.