AbstractA method is described for constructing geometrically the two‐dimensional electromagnetic wave in an inhomogeneous anisotropic medium. An example of application is also shown. Since the basic theory has already been reported, an application algorithm is described here in detail. Especially, the geometrical optics field at an arbitrary time is traced numerically after the initial shape of the wavefront and the initial intensity profile of the electromagnetic field are given. In the example, a uniaxial anisotropic medium with a weak inhomogeneity is assumed and the initial intensity profile of the geometrical optics field is taken Gaussian.