Abstract: Quasi-Saturated soil consists of solid particles,water and a small amount of trapped air The method and correspondingformula to study explosive wave propagation and soil-structure interaction in non-saturated soil are not valid for quasi-saturated soil.In addition,the dynamic properties of the quasi-saturated soil is alse different from that of the two-phase mixture media consistingof soild partides and water(regarded as saturated seil).In this paper,the mixture theory is used to establish the dynamic modelbased on macraseopic test results in the quasi-saturated soil under one-dimensional plane explosive wave.