Abstract: A reactive distillation for the synthesis of methyl lactate with excess lactic acid feed was designed to improve the low efficiency in reactive distillation process of methyl lactate due to the unfavorable boiling points sequence of the highest boiling points of lactic acid and the lowest boiling point of methanol. Taking the annual total cost (TAC) as the objective function, the operating and structural parameters were optimized by the sequential optimization method. The results show that the minimum TAC was 3.05×10⁶ CNY·a^-1 under the optimal operating conditions: excess ratio of 1.3, reactive section stages of 7 and stripping section stages of 16 (including reboiler) in reactive distillation column. Compared with the reactive distillation process with proportional feeding, the reboiler duty and TAC of the process with overfeeding decreased by 70.4% and 51.2% respectively.