Ash gourd (Benincasa hispida) is valued for its nutritive and medicinal properties and further value addition is being attempted by fermentation process. In the present study, the optimization of the fermentation process with reference to yeast concentration and the period has been attempted by using RSM. The statistical design gave 13 formulations, where yeast concentration was from 1 to 5.8% and the fermentation process period varied from 0.5 to 17.5 days. The product varied formulations had total phenols ranged from 24.8 to 43.6mg%, antioxidant 12.3 to 27%, acidity 0.067 to 0.6%, total volatiles 0.0025 to 0.078%, alcohol 4.6-12.4%, overall acceptability 6.9 to 8.4, thiamine 115.7 to 367 µg%, riboflavin 32.4 to 159 µg%, niacin 6.7 to 139.4 µg%, pyridoxine 71.68 to 174.1 µg% and vitamin C from 0.02 to 0.21mg%. Yeast concentration of 3% and fermentation time for 3 days was the optimized process conditions achieved with the best fit of desirability 0.92.