Abstract: In order to study the influence of rheological properties of rock mass on long-term stability of minted-out area, a rheological mechanics model of pillar-roof is constructed based on Reissner thick plate and rheological mechanics theory, and the equation of subsidence displacement of roof with respect to rheological time is derived.The roof failure process is divided into four stages:clamped-clamped, clamped-pinned, pinned-pinned and internal damage stage based on the different boundary conditions.The results show that the rheological mechanics model can be applied to predict the stabilization time of mined-out area and provide reference for timely processing.