Abstract:A new RIC preconditioned conjugate orthogonal conjugate gradient(COCG) iterative method is presented for solving the highly indefinite linear equations, which is arised from the finite element method(FEM) for analyzing optical and electrical engineering problems. The proposed RIC preconditioner is based on the basic IC algorithm and aiming at solving the breakdowns during the factorizing process. By adding compensation to the pivots, RIC process can be more stable thus generating the more effective preconditioner. Numerical examples show that, the proposed RIC preconditioner can not only avoid the isotropic breakdown of COCG, but also can be more effective than other typical ones; moreover, RIC can dramatically improve the performance of several other Krylov subspace iterative methods.