Abstract: The aim of this paper is to investigate the phase behavior of glycerol, 1,2-propanediol, water, and nicotine in heated cigarettes, and explore the influence of temperature and composition (in mole fractions) on the release of nicotine during vaporization. Conductor-like Screen Model for Segment Activity Coefficient (COSMO-SAC) was employed to study the vapor-liquid phase equilibria of ternary and quaternary systems composed of glycerol, 1,2-propanediol, water, and nicotine. For the glycerol-1,2-propanediol-nicotine system, an increase in glycerol mole fraction in the liquid phase promotes the release of nicotine during vaporization. Lower temperatures are more favorable for the vaporization of nicotine. For the glycerol-water-nicotine system, the variation of glycerol composition over a certain range does not significantly change the gas phase composition. Only when the mole fraction of glycerol exceeds 0.9, lower temperatures are more favorable for the vaporization of nicotine. For the water-1,2-propanediol-nicotine system, lower temperatures are more favorable for the vaporization of nicotine when the mole fraction of water is less than 0.3 or greater than 0.7. For the water-1,2-propanediol-glycerol-nicotine system, the change of liquid phase composition over a wide range does not significantly change the gas phase composition, that is, the gas phase composition has a wide platform region.