This study deals with an experimental work that aims to examine the effects of nanoparticles added to diesel fuels. Nanodiesel fuels were prepared by adding aluminum oxide and copper oxide nanoparticles. These nanoparticles were blended with diesel fuel in varying mass fractions by the means of amechanical homogenizer and an ultrasonicator. Physicochemical properties of nanodiesels were measured and compared with neat diesel fuel. Their stability characteristics were analyzed under static conditions. The effects of the additive nanoparticles on the engine performance and emissions were also investigated. The results showed that the stability of nanodiesel can be increased by regulating pH and using dispersant. The storage and combustion characteristics were also improved by adding nanoparticles. The engine test results indicated that the nanodiesel in terms of engine performance efficiency and environmentally friendly emissions could be recognized as the potential candidates in diesel engines. (C) 2015 Elsevier Ltd. All rights reserved.