It is of great necessity to study on hysteresis phenomenon of soil-water characteristic curve(SWCC),for it plays an important role in observing engineering behavior of unsaturated soils.For this,the mechanism and influential effects of the hysteresis SWCC were discussed firstly in this paper,then the principal and quality of various hysteresis models were compared.Based on these,the theory of independent domain model was introduced to study hysteresis pheonomenon of SWCC,and according to features of each st...