Pressure swing distillation for separation of methanol and methyl ethyl ketone was investigated based on thepressure-sensitivity of azeotropic composition. Taking the lowest total heat load of reboiler of the high pressure and atmospheric pressure towers as the optimization objective, the theoretical plate number, feed position and mass reflux ratio of the two towers were optimized. The optimum process parameters were obtained as follows: high pressure tower operating pressure 300kPa, theoretical plate number 37, feed position 22, reflux ratio 2.5; atmospheric tower operating pressure 101.3kPa, theoretical plate number 48, feed position 11, reflux ratio 4.25. The mass fractions of methanol and methyl ethyl ketone are 99.75% and 99.53%, respectively. On the basis of ordinary pressure swing distillation, the system is fully heat integrated. Compared with ordinary pressure swing distillation, the heat load of the condenser of fully heat-integrated pressure swing distillation reduces by 48.07% and the heat load of reboiler decreases by 47.62%, which realizes effective energy saving.