Abstract: From analyses of a large amount of well data and application of the theory of plastic flow with reference to the geologic features of the basin, the cause of frequent premature casing failure in the Jianghan salt-lake basin is studied. It is pointed out that when a plastic rock like rock salt is buried to a certain depth, the gravity loading pressure of the overburden may, under the action of differentiation, result in a plastic flowing pressure of 0.24 kg/cm² commensurate to that for an average of each meter of burial of the overburden. The author believes that the resulting lateral compression stress in excess of the compression load of casing is the primary csuse of the frequent premature casing failure in Jianghan. He therefore proposes to raise the compressibility coefficient of the casing for the rock-salt section to 0.24 Kg/cm²/meter as a principal preventive measure to be introduced in Jinaghan.