A detailed numerical study has been performed to investigate the evaporative cooling of liquid falling film through interfacial heat and mass transfer in turbulent mixed convection channel flows. The effects of gas-liquid phase coupling, variable thermophysical properties and film vaporization are considered in the analysis. Simultaneous mass, momentum and heat transfer between liquid film and gas stream is numerically studied by solving the respective governing equations for the liquid film and gas stream together. In the gas stream, the low Reynolds number turbulent k-epsilon model has been used to simulate the turbulent flow. Results are presented for an air-water system under different conditions.＇ Particular attention is paid to investigating the role of latent heat transport associated with the film vaporization. Results show that the heat transfer from the gas-liquid interface to the gas stream is predominantly determined by the latent heat transfer connected with film evaporation. Additionally, better liquid film cooling is noticed for the system having a higher inlet liquid temperature T-li, a lower liquid flowrate B or a higher gas flow Reynolds number Re.