Abstract: Based on the damage feature of large broken zone in the surrounding rock,the supporting mechanism of combined support of bolting-grouting and prestressed cable anchor was studied with theory analysis,test and engineering practice;the supporting theory is put forward that the broken rock zone could be strengthen by the bolting-grouting support,and the strength of the deep rock of the surrounding rock could be well utilized by the prestressed cable anchor,furthermore,the combined support could form multiple reinforced rock structure which could completely control the bad damage of the broken rock zone.Finally,The technology was applied into practice and satisfying result was acquired.It was proved in the industrial trial to be reliable,convenient and economic,possessing a wide spread value in civil engineering.