Abstract: The making and structure of Ag-AgCl solid-state electrode with high mechanical strength and low internal resistance(1～2kΩ)is deseribed. Experiments show that buried in 8 different soil media at room temperatures 8～26℃ for several to over 20 days, the potentials of Ag-AgCl electrodes remain basically steady, with a maximum waving of not more than 10 mV. Measurements of steadystate polarization curves for Ag-AgCl electrodes buriedin 4 different kinds of soil saturated with water indicate that when the electrodes are used jointly with the potentiostat with input impedance of more than 15 MΩ, the electrode potential drift caused by the current flowing through the electrodes would not exceed 10 mV.