Jatropha curcas cake has been studied to produce the bio-oil in a fixed bed pyrolysis unit (slow pyrolysis). The effect of pyrolysis temperature on the product yield and composition was investigated. The highest yield of bio-oil was obtained at 550 degrees C with the heating rate of 5 degrees C/min for the particle size of 0.5-0.8 mm. The physicochemical characteristics of optimum (maximum yield) bio-oil have been completed. The empirical formula of the bio-oil with a calorific value of 25.91 MJ/kg is C-23.19 H-53.53 N O-10.78. The physicochemical characterization studies of the bio-oil showed that the bio-oil obtained from the jatropha curcas cake might be a valuable source for conventional fuel. Chemical composition of the bio-oil has been also investigated by H-1 and C-13 NMR spectroscopy.