Continuous rectification of industrial dipentene in vacuum was simulated by Aspen plus. Effects of feed stage, reflux ratio, distillate to feed ratio and operation pressure on limonene purity and reboiler energy consumption were investigated and the optimum conditions for distillation were obtained as follows: the theor. plate number 65, feed stage at thirtieth, reflux ratio 4:1, distillate to feed ratio 0.7, top stage pressure 6 kPa, and the column pressure drop 12 kPa. Limonene with the purity of 71.5% and the distillate to feed ratio of 70% was obtained in production experiment, which is similar to the simulation results.