Recently many researchers have been studying the development of alternative energy due to serious environmental pollution and drying up fossil energy. Among various alternative fuels, authors investigated the physical and combustion characteristics of the bio diesel fuel(BDF) which was made from the wasted vegetable oil. In this study, PXI and LabVIEW, which is a novel measuring instrument and online analysis, was used to investigate the combustion characteristics of BDF in a DI diesel engine.