The coercive forces and the magnetic domains of thick permalloy films which were prepared by evaporation under different conditions such as substrate temperature, vacuum pressure and substrate materials have been studied. B-H loops, magneto-optical Kerr method, Bitter pattern observations and the internal stresses of the films were measured. The value of the coercive force and the magnetic domain of the permalloy films could be explained by the magnitude of the internal stress. Moreover, layered films which consist of a uniaxial anisotropic layer and a stripe domain layer have been found.