Droplet vaporization in a high-pressure and temperature stagnant environment has been investigated numerically. Results are presented for a n-hexane droplet evaporating into nitrogen, for ambient pressures of 1-100 atm and temperatures of 500-1250 K. The high-pressure model accounts for 1) transients hi both the liquid and the gas phase; 2) real gas effects hi calculating the gas phase density, the energy required for phase change, and the droplet surface vapor-liquid equilibrium composition; and 3) it accounts for gas phase transport and thermodynamic properties varying with temperature, pressure, and composition. The droplet lifetime dependence on ambient pressure and temperature has been predicted. At the lowest ambient temperature considered (500 K), the droplet lifetime increases monotonically with ambient pressure, at least for the pressure range investigated. At a higher ambient temperature of 600 K, it exhibits a maximum with ambient pressure. At an ambient temperature of 1000 K, the droplet lifetime is less sensitive to pressure. At even higher ambient temperatures (1250 K), it decreases monotonically with pressure. The steady-state vaporization assumption underpredicts droplet lifetimes substantially with increasing ambient pressure.