This article deals with an experimental work that aims to examine the effects of MWCNTs dispersed into diesel fuels. Nano diesel fuels were prepared by dispersing multi-walled carbon nanotubes into base liquid. The MWCNT nanomaterial was mixed in the fuel blend along with a surfactant by means of an ultrasonicator, to attain stable dispersion. Physicochemical properties of nano-additive based diesel were measured and compared with pure diesel fuel. Physicochemical properties of nano-additive based diesel were measured and compared with pure diesel fuel. An experimental investigation was performed at a constant speed of 1500 revolution per minutes at different engine load conditions. The engine performance and exhaust emissions of a diesel engine burning MWCNTs were compared with pure diesel fuel. MWCNTs to diesel oil is effectively enhancing the performance and decreasing exhaust emissions in a diesel engine. The properties of N80 + JB20 with MWCNT fuel blend are changed owing to the mixing of biodiesel and the combination of the MWCNT nanomaterials. © 2019, © 2019 Taylor & Francis Group, LLC.