The paper presents a method to optimize the location and the dimensions of the corona ring for transmission line composite insulators using finite element based software, FEMLAB. The procedure used to optimize the corona ring design, which handles more than one parameter, has been verified with examples that have an analytical solution or known optimal values. In this work the optimization is based on finding the maximum field along the insulator surface, such that this maximum field is well below the corona inception level. The design parameters of the ring diameter, diameter of the ring tube, position of the ring in its vertical plane, and the maximum field that cannot exceed the corona inception level have been used in the optimization process.