One of the major problems in the contemporary world is pollution. The major contribution in this area comes from automobile emissions and industries. Diesel being one of the major fuels is also a major contributor in adding harmful pollutants into the atmosphere. In order to meet the stringent emission norms, the polluting components in the fuels need considerable reduction. Fuel characteristics play a major role in engine efficiency and engine emissions directly or indirectly. In the present work, an experimental investigation of the effect of adding methanol to the diesel-biodiesel blends on the performance and combustion characteristics of the diesel engine has been performed. Three different concentrations of methanol are used; namely 5%, 7%, and 10% of the overall mixture volume, while, biodiesel concentration has been fixed to eliminate its effect on the results. The results revealed that using methanol as an additive to the diesel-biodiesel blends prominently improved brake power, decreased brake specific fuel consumption (BSFC) and increased brake thermal efficiency (BTE) of the engine. CO, HC, and NOx emissions have shown a slight decrease compared to the corresponding neat diesel and diesel-biodiesel at the same loading and engine speed conditions.