Buckling mechanism (BM) plays a dominant role when we need to form convex shape in the high-frequency induction heat forming. To explore deformation behavior of metal plate under BM, in this paper, a 3D finite element simulation has been carried out accounting for geometric and material nonlinearities. Effect of parameters on bending angle, including effective power of inductor, coil diameter, moving speed and thickness of plate, is studied. Using similar method as in laser forming, an inequality which can distinguish the bending direction is obtained, and the analytical results are good agreement with the numerical results. To predict bending angle of metal plate under BM, an analytical model has been derived based on similarity of temperature distribution. The analytical results are experimentally validated.