Abstract: The problem of reasonable width of deep isolated island working face has always been an unresolved erosion-control difficult problem in coal mine site.Taking the 30207 designed isolated island working face in Mudu Chaideng Mine of Erdos as the engineering background,theoretical analysis method is used to study the design method of reasonable width of deep isolated island working face based on erosion-control.The load distribution law of isolated island working face under the condition of different goaf widths on both wings is explored and discussed.Based on the theory of load three zones,an estimation model for the load-bearing stress of isolated island working face is established.The height division model of the overlying load three zones of isolated island working face is studied,and the erosion-control critical width estimation method of deep high stress isolated island working face is designed.The results indicate that the theoretical safe width of the isolated island working face in the case checking calculation should not be less than 245 m.Considering the influence of strong dynamic loads,the reasonable width of the isolated island working face based on erosion-control applied on site is 300 m.