Objective To improve the image quality of the electrical impedance tomography (EIT) by introducing the prior information into the regularization matrix.Methods The linear combination of the conductivity was established by background conductivity of dynamic variation,the covariance matrix was used here to remove the correlation between the background conductivity,and this prior information was introduced to construct the regularization matrix.Resnlts Compared with the traditional regularization matrix,the one involving in the prior information on the dynamic background gained more stable and better images.Conclusion Trials prove the efficacy of the regularization matrix on EIT imaging in 1 respiratory cycles (or heart beat),and following related researches may find theoretical references and support for feasibility.