The underground mining circumstances is bad, in order to accurately locate the stratum subsidence due to underground mining and discover the movement rule of stratum, the rock displacement brought by exploring was measured accurately using automated grid methods based on the similar material model. This paper detailedly discusses the experimental procedures of the automated grid methods, advances a kind of new image - matching rectifying method, and makes use of actual data of the displacement to explain the feasibility and insufficiencies of this method.