Abstract: Under the ground-load effect the ground distortion and stability of engineering building estate above underground roadway are evaluated by the random medium theory.In the light of structural character,geologic and retaining conditions the rock mass is regarded as random medium and the ground subsidence in digging soil and rock as random course.As a result it is possible to simulate the stress and straining of soil and rock surrounding roadway in different engineering conditions and carry through ration assessment,resulting assessment conclusions of estate stability,the most gradient and ground subsidence.