Mining technology and geological conditions made a difference in destruction of coal seam mining face. Impact analysis of permeability and strain stress of seam floor was given through experiment measures. Based on data analysis, it was clear that rock permeability would be incresed significantly by increasing stress because of densification effect of air space ratio and fracture. As a result, increase of deformation damage would cause rock permeability,and then induced flooding accident. This analysis contributed to enhance safety evaluation of coal mining.