Laser　surface　texturing　(LST)　followed　by　ultrasonic　surface　rolling　(USR)　was　applied　to　20CrMoH　steel　to　improve　the　friction　and　wear　behavior.　In　this　paper,　the　fretting　friction　and　wear　mechanisms　of　the　modified　(USR,　LST　+　USR)　20CrMoH　steel　under　different　loads　and　lubrication　conditions　were　systematically　investigated.　Results　indicated　that　the　regular　coupling　distribution　of　micro-texture　and　gradient　nanostructure　(GNS)　was　formed　on　the　surface　layer　of　the　combined　treated　material.　Simultaneously,　the　depth　of　the　GNS　was　up　to　22　μm　and　the　surface　microhardness　was　increased　from　800　HV0.2　to　860　HV0.2.　Besides,　the　surface　roughness　Ra　value　was　decreased　from　0.24　μm　to　0.01　μm　and　the　maximum　residual　compressive　stress　(RCS)　value　was　−610　MPa.　Under　dry　friction　and　high　load　conditions,　compared　with　the　untreated　specimen,　the　average　friction　coefficient　and　worn　losses　of　the　combined　treated　specimen　were　reduced　by　about　10%　and　30%,　respectively.　In　comparison　with　the　untreated　specimen,　the　average　friction　coefficient　of　the　combined　treated　specimen　was　decreased　by　26%　under　the　conditions　of　low　load　and　oil　lubrication.　Especially,　the　fretting　wear　resistance　was　obviously　improved　and　its　worn　loss　was　significantly　reduced　by　92.05%　compared　with　the　untreated　material.　The　predominant　wear　mechanisms　of　the　combined　treated　material　under　dry　friction　and　oil　lubrication　were　oxidation　wear　and　abrasive　wear,　respectively.　©　2021　Elsevier　B.V.