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In order to study the electrical response characteristics of sandstones after high temperature, uniaxial compression tests were carried out on green sandstone samples at room temperature and heated at 200, 400, 500, 600 and 800 °C, and the change law of resistivity during compression was monitored in real time. The results showed that corresponding to the compaction stage, stable crack growth stage, rapid crack growth stage and failure stage of rocks under uniaxial compression, the resistivity change of water-cooled high temperature sandstones shows four stages: small increase, steady increase, significant increase and sharp decrease of resistivity. When the heating temperature is lower than 400 °C, the resistivity changing rate in the initial compaction state is under 10%, while when the heating temperature is over 400 °C, the changing rate of resistivity increases and can be up to 50% when the heating temperature is 800 °C. This indicates that the changing rate of resistivity can reflect the incipient damage degree in rocks. When the compressive pressure reaches 80% ～ 90% of the peak strength, the changing rate of resistivity reaches its peak value, and then decreases sharply, which can be used as a precursor of rock failure. The anisotropic characteristics of resistivity change can indicate the location of the penetrated crack in such a way that the most significant change of resistivity can be observed near the upcoming penetrated crack. [ABSTRACT FROM AUTHOR]