Ceramic-based　composites　have　been　applied　to　turbine　components　of　new-generation　aerospace　engines　due　to　their　excellent　properties.　Despite　the　superior　high-temperature　resistance　of　SiC/SiC　composites,　it　is　necessary　to　combine　with　film　cooling　technology　to　guarantee　normal　function　of　turbine　components.　However,　SiC/SiC　composites　are　typical　difficult-to-process　materialsand　the　depth　of　film　cooling　holes　have　increasingly　high　requirements,　which　have　become　one　of　the　major　problems　in　the　manufacturing　of　aerospace　engine　turbine　parts.　In　this　paper,　the　spatial　energy　density　distribution　based　on　filament　effect　of　femtosecond　laser　was　theoretically　studied,　it　is　revealed　that　the　filament　effect　of　femtosecond　laser　with　high　single　pulse　energy　will　lead　to　the　peak　of　energy　density　shift　towards　the　negative　defocus　direction.　Based　on　the　theoretical　research,　the　experimental　study　on　the　processing　of　deep　micropore　in　SiC/SiC　composites　by　femtosecond　laser　was　carried　out,　main　results　show　that　in　equal　conditions,　the　depth　of　micropore　in　feed　trepanning　is　deeper　than　that　in　trepanning,　and　that　in　trepanning　is　deeper　than　that　in　direct　punching.　This　research　provides　both　theoretical　and　technical　support　for　processing　of　micropore　with　high　aspect　ratio　by　ultrafast　laser　on　the　difficult-to-process　materials,　which　have　high　practical　value　in　the　aerospace　field.　©　2021