Abstract: Ignoring the coupling effect between metamaterial unit cells, traditional transmission / reflection method shows error in calculating the effective electromagnetic parameters. To address this issue, this paper discusses the coupling and compensation method of unit cells in different directions, and proposes an improved transmission / reflection method based on bi-directional coupling compensation. The results of this improved method indicate that comparing with traditional methods, this method  can effectively predict multiple resonant regions, and calculate electromagnetic parameters of the whole material more accurately.The simulation results fit well with the results by using Ansoft HFSS software, but the corresponding computing time and hardware requirements of this method are obviously reduced due to the application of local modeling computation.