The　grey　incidence　analysis　is　applied　in　the　screening　of　disc-brake　pair　materials　of　drilling　rig,　based　on　variable-temperature　friction　and　wear　tests　of　six　kinds　of　brake-disc　materials　paired　with　two　kinds　of　brake-block　materials.　The　tribological　performance　indicators　of　the　brake-pair　materials　to　be　screened　are　quantified　by　grey　incidence　degree　based　on　comprehensively　analyzing　each　performance　indicator　of　the　brake-pair　materials.　The　brake-pair　material　with　better　performance　can　thus　be　screened　by　quantitative　arrangement　of　the　incidence　degree　of　the　brake　pairs.　It　has　been　found　that　the　B　welded　material　and　the　K2　friction　material　can　be　selected　as　the　best　brake-disc　and　brake-block　material,　respectively.　Therefore,　the　frictional　pair　materials　P20,B/K2　and　P35,B/K2　are　screened　as　the　optimum　brake-pair　materials.