The　multilayer　gradient　TiN/Ti　coating　was　deposited　by　using　filtered　cathodic　vacuum　arc　(FCVA)　deposition　method.　The　laser　shock　peening　(LSP)　process　was　carried　out　before　deposition.　The　surface　morphology,　mechanical　properties　were　measured　by　atomic　force　microscope　(AFM),　nanoindentation　and　scratch　tester.　The　fatigue　strength　was　investigated　on　a　vibration　test　platform　and　the　fracture　morphologies　were　observed　by　scanning　electron　microscope　(SEM).　The　results　showed　that　the　compound　process　has　little　negative　influence　on　the　roughness.　A　hardened　layer　with　high　hardness　and　compressive　residual　stress　was　formed　by　the　LSP　pre-treatment.　This　layer　can　also　suppress　plastic　deformation,　making　the　adhesion　strength　between　the　coating　and　substrate　increased　from　54.9　N　to　79.1　N.　The　TiN/Ti　coating　and　the　compound　process　improve　the　fatigue　strength　of　TC4　alloy　by　58.1%　and　98.8%,　respectively.　The　coating　can　restrain　crack　initiation　on　the　surface　and　slow　its　propagation.　The　crack　initiation　location　of　the　compound　process　sample　moved　into　the　deeper　site　and　the　improved　adhesion　strength　further　reduces　the　crack　propagation　rate.　Thus,　the　compound　process　of　TiN/Ti　coating　combined　with　laser　shock　peening　pre-treatment　greatly　improves　the　fatigue　strength　of　TC4　alloy.　©　2020　Elsevier　B.V.