Concerns about long term availability of petroleum based fuels and stringent environmental norms have been a subject for deliberations around the globe. The vegetable oil based fuels and alcohols are very promising alternative fuels for substitution of diesel, reduce exhaust emissions and to improve combustion in diesel engines which is mainly possible due to oxygenated nature of these fuels.Jatropha oil is important non-edible oil in India which is either used in neat or modified form as diesel fuel. Furthermore n-butanol is renewable higher alcohol having properties quite similar to diesel fuel. In the present study, n-butanol was blended in Jatropha Oil (JO) and Jatropha Oil Methyl Ester (JME) on volumetric basis (10 and 20%). The blends were homogeneous and stable and there was no phase separation. The different physicochemical properties of blends were evaluated as per relevant standards. The performance and emission characteristics of a single cylinder, unmodified diesel engine we evaluated on these blends and results compared with base line diesel.The results suggests that brake thermal efficiency (BTE) was found to increase with increase in volume fraction of n-butanol in vegetable oil based fuels. Also brake specific energy consumption was found to decrease with increased amount of n-butanol. The reduction in smoke opacity, oxides of nitrogen (NOx) and carbon monoxide (CO) emissions was observed with addition of n-butanol, however, hydrocarbon emissions increased with substitution of n-butanol.