Abstract: Abstract: Due to the increase of open-pit exploration,shortage of land resources and the influence of large geological structure, so many old dumps have to increase capacity,that induced the security problem increasingly prominent．Taking a waste dump of Antaibao open-pit coal mine as a case,the feasibility for the capacity increase and heightening of the dump was analyzed under the influence of anticline structure by the methods of basal bearing capacity analysis and limit equilibrium analysis．Through the optimization analysis, the generally flat width narrowed to 65 m, the overall slope Angle increased to 19°and the residual displacement space increased to 334.8 million m3.Effectively alleviate the problems of internal waste dump can't timely follow up and serious insufficient displacement space,ensure the normal advanced stripping work.Research methods and results worth widely using for reference.