Isospin mixing probabilities in the N = Z nuclei towards the proton drip-line nucleus 1 0 0 Sn are evaluated using the deformed Hartree-Fock solutions with the Skyrme interaction. The mixing probability is proportional to only slightly lower power in Z than Z 8 3 obtained from the hydrodynamical estimate by Bohr and Mottelson, however, it is larger by a factor of about 2.