Abstract: Numerical simulation of large-scale and complex model of electromagnetic field is always difficult problem in electromagnetic calculation. In this paper, a parallel algorithm for 3D adaptive finite element method is used to deal with this kind of problem. Taking the simulation of full model of the valve hall for a ± 660kV converter station as example, the electric field value on the surface of fittings in each interested region is calculated. Parallel computation is well consistent with the results of serial computation. So the correctness and feasibility of proposed parallel algorithm is verified. This parallel algorithm can improve calculation speed obviously to realize efficient numerical simulation for large-scale complex electromagnetic problems.