Abstract: In the research, a stable isotope ¹⁸O separation column was set up by water vacuum distillation with 20 m packing height and 0.1 m diameter of the column. The self-developed special packing named PAC-¹⁸O was packed inside the column. Firstly, a model was created by using the Aspen Plus software, and then the simulation results were validated by test results. Secondly, a group of simulation results were created by Aspen Plus, and the optimal operation conditions were gotten by using the artificial neural network (ANN) and Statistica software. Considering comprehensive factors drawn from column pressure and from withdrawing velocity, conclusions were reached on the study of the impact on the abundance of the isotope ¹⁸O. The final results show that the abundance of the isotope ¹⁸O increases as column pressure dropping and withdrawing velocity decreasing. Besides, the optimal column pressure and the incidence formula between the abundance of the isotope ¹⁸O and withdrawing velocity were gotten. The conclusion is that the method of simulation and optimization can be applied to ¹⁸O industrial design and will be popular in traditional distillation process to realize optimization design.