Femtosecond　laser,　one　of　the　ultra-fast　lasers,　was　used　to　irradiate　4H-SiC　wafers　to　modify　the　morphology　and　mechanical　properties　of　the　surface.　The　modified　surface　could　exhibit　a　surface　feather　of　laser-induced　periodic　surface　structure　(LIPSS).　To　investigate　the　machinability　of　modified　SiC　surface,　the　mechanical　properties　of　the　modified　surface　was　characterized　by　nanoindentation.　The　influence　of　laser　processing　parameters　on　the　LIPSS　structure　and　mechanical　properties　was　also　studied.　And　the　mechanical　properties　such　as　hardness　and　elastic　modulus　of　each　surface　were　investigated.　The　results　show　that,　within　a　certain　range,　with　the　increase　of　the　scanning　speed,　the　ripple　period　formed　on　the　surface　of　SiC　gradually　increases;　the　surface　hardness　and　elastic　modulus　of　the　modified　layer　are　greatly　reduced,　and　with　the　increase　of　the　depth,　the　hardness　gradually　approached　that　of　the　unmodified　SiC,　and　the　hardness　of　the　three　modified　surfaces　also　varied,　but　it　does　not　change　linearly　with　the　increase　of　the　ripple　period.