Abstract: Drunk with hot water by intubation (75^oC), the mouse were observed with thre ? kinds of change in the forestomach mucosa. They were( 1) degeneration of the epithelial cell and inflammation of the mucosa, (2) decrease of 3H-TdR labelling index (P<0.01), which means prolongation of Gi stage. It indicated that superheat food and drink could affect nucleic acid metabolism of the celli (3) tie bacteria reproducted and contacted with the epithelial cell, which may be utilized as a beneficial condition of the cancer reaction of the cell under the effect of some toxic metabolic productions.