A Study of the interaction between the behaviour of forest fire and associated air motion is very important for extinguishing the fire. A two-dimensional non-linear quasielastic model of air motion associated with severe temperature disturbance was developed. The structure and evolution of air motion and temperature fields associated with forest fire under three kinds of conditions were simulated, which are calm atmosphere, vertically sheared wind and spreading fire with surface wind. The results were reasonable. Differences of air motion and heat transfer under these conditions were investigated and the surface reverse wind was analyzed.