This project aims at a comparative study on performance, emission, and combustion of banana peel and bran oil when blended with diesel in a single cylinder four stroke water cooled direct injection diesel engine. Because of modernizations and increase in number of automobiles worldwide, the consumption of diesel has massively increased. As petroleum is a non-renewable major source of energy and its reserves are scare nowadays, there is a need for research in finding alternative fuels for automobiles. And also biodiesels are renewable, nontoxic, and eco-friendly fuels that can play an important role in the automobile industries. Based on the above facts various studies and investigations are carried out with different vegetable oils to prepare cost effective and reduced NOX with improved efficient biodiesel. After the intensive study, the identified was banana peel & bran oil. The intensive focus of alternative fuels for the compression ignition engines has been extracted from banana peel & bran oil is found to be potential fuel for CI engines. The properties of banana peel & bran oil are determined by using standard techniques and properties are compared with diesel.