In these studies, the microwave-assisted transesterification of non-edible Papaya oil was investigated under the fixed microwave power of 700 W and constant magnetic stirring. Optimization of the yield of Papaya oil methyl ester was investigated using response surface methodology. Within the range of the selected operating conditions, the optimized values of temperature, catalyst amount, time, and methanol to oil molar ratio were found to be 62.33 degrees C, 0.95 wt %, 3.30 min, and 9.50:1 respectively. Current studies revealed that the methanol to oil molar ratio and temperature have significant effects on microwave assisted transesterification of Papaya oil. The high values of R-2 97.72 and R-adj(2) 95.60 indicate that the fitted model shows a good agreement with the predicted and actual FAME yield. Based on the optimum condition, the predicted biodiesel yield was 99.9% and the actual experimental value was 99.3%. Papaya oil methyl ester (POME) exhibits property close to ASTM standards. In conclusion, these studies revealed that biodiesel obtained from Papaya seed oil feedstock has a potential to use as an alternative of diesel. (C) 2019 Elsevier Ltd. All rights reserved.