Optimization of the key process parameters of solvent extraction of Terminalia catappa L (TC) oil was carried out using response surface methodology (RSM). Effects of temperature, particle size and extraction time on the oil yield were evaluated. The process fitted (R 2 = 96.94%) to the second order quadratic model while interactions of process variables were significant on the oil yield. The optimum parameters were obtained at 55°C, 0.5 mm and 150 min for 60.45% oil yield. The color of TC oil was pale yellow with dielectric strength of 30.61KV, which is considered acceptable in comparison with International Electrotechnical commission (IEC) standards. Free fatty acids of saturated and unsaturated oils were 42.95% and 56.1%, respectively. The physicochemical properties of oil indicated its potential for application as transformer fluid