The processes of heat and mass transfer at the ignition of air and typical combustible liquid vapors mixture by a moving single metal particle heated till high temperatures are numerically investigated. The researches are carried out on the base of gas phase ignition model considering processes of heat conductivity, liquid evaporation, diffusion and convection of fuel vapors in oxidizing medium, ignition source crystallization, kinetic of evaporation and ignition processes, dependences of thermo physical properties of interacting substances from temperature, air humidity, heating source movement in vapor and gas mixture. The dependences of main characteristic of investigated process – ignition time delay from rate of particle motion, air humidity and temperature, distance between heating source and liquid surface, initial temperature and sizes of particle are determined.