A GA- based approach for accurate modeling of sphere-plane gaps using the point charge simulation method is presented. Optimal arrangement of the simulating charges locations, expressed in spherical coordinates, are automatically arrived at using GA to eliminate dependency on the user experience and judgment. Accurate results, compared with earlier published techniques, are achieved for a wide range of field non-uniformity factor. Recommended assignment factors, based on optimum charge locations, are also derived and presented. The present work shows that the GA can be useful to, automatically, determine the appropriate arrangement of fictitious charges efficiently for accurate field computations.