By taking into account its high amount of oil in its seeds (1892 L/ha), competitiveness with food, planting conditions and drought resistance, jatropha curcas oil is the best to be a raw material for the production of biodiesel. Advantageously, catalysts prepared from heterogeneous base catalyst could make the biodiesel product more sustainable, environmentally friendly and cost-effective. The main objective of this study is focused on the investigation of NaOH impregnated acid treated fly ash catalyst as heterogeneous solid base catalyst for transesterification of jatropha curcas oil. The prepared catalyst was characterized by powder X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR) and thermo-gravimetric analysis (TGA). The prepared catalyst had a high catalytic activity at 3:1 mass mixing ratio of metal hydroxide to acid treated-fly ash. In addition, the reusability results of the prepared catalyst confirmed that it could be used repeatedly for five times with good conversion of 92.3, 92, 90.8, 88.5, 77%, respectively. The experimental results revealed the maximum FAME yield of 96.3% at the optimal parametric conditions viz. methanol/oil molar ratio, 9:1, at a temperature of 70°C, and catalyst concentration, 5 wt.% of oil. The experimental design and statistical analysis were done by Design-Expert 11 program and response surface methodology was used to optimize the biodiesel production. The produced biodiesel important fuel properties are compared well with ASTM biodiesel standard and the engine performances like brake powers, brake torque and brake specific fuel consumption were also evaluated by CT 400.02 Four-cylinder diesel engine. Numerically, the maximum brake torque for the produced biodiesel and diesel is 11.9Nm, and 10.4Nm, respectively at 2400rpm and the brake power varies from 1.25 to 1.87kW and 1.31 to 2.29kW, respectively. The brake specific fuel consumption varies from 0.177 kg/kWh at low speed to 0.112 kg/kWh at high speed for biodiesel, and it varies from 0.169 kg/kWh to 0.106 kg/kWh for diesel. Despite some variations in power and time to reach maximum power, it is feasible to conclude that the biodiesel produced is a better alternative fuel in terms of meeting the required brake torque and break power. Keywords: Engine performance, Fly ash, Transesterification, Jatropha oil, Biodiesel