Objective To establish intra-body communication(IBC)model with quasi-static approximation and validate its correctness.Methods The quasi-static approximation conditions of human tissues were discussed.Based on the Maxwell Equations,the model of galvanic coupling IBC was developed analytically.It was assumed that the human forearm was equal to column with a pair of ring electrodes.Sausage column was selected to be the experimental object for validating the correctness of the model.Results Galvanic coupling IBC model was established.The deviation of model calculated results from test measured potentials was less than 10%,and the correlation coefficient was more than 0.998.The potential distribution and attenuation were depicted with the model.Conclusion Under quasi-static approximation condition the galvanic coupling IBC electromagnetic theoretic model is developed and validated.It is provided the preliminary theoretic base on IBC technique.