In the strong correlated perovskite-type copper fluoride of K 2 CuF 4 , the degree of freedom in d orbitals of copper cation should be considered to understand the magnetism. We performed the cluster model calculations under consideration of octahedral fluorine anions around copper cation, in order to investigate the magnetism. At the amplitude of Jahn–Teller distortion, the alternate dz2-x2 type orbital ordering and the experimental effective exchange integral (J ab ) value were reproduced. The calculated potential energy curves were discussed, from the viewpoint of the theoretical total energy in the Jahn–Teller distorted structure proposed by Kanamori.