In　this　paper,　free　vibrations　of　functionally　graded　(FG)　graphene-reinforced　composite　blades　with　varying　cross-sections　are　investigated.　Considering　the　cantilever　boundary　conditions,　the　dynamic　model　of　a　rotating　blade　is　simplified　as　a　varying　cross-sections　plate　with　pre-installed　angle　and　pre-twisted　angle.　As　a　reinforcement,　the　graphene　platelets　(GPLs)　are　distributed　either　uniformly　or　gradiently　on　the　plate　along　its　thickness　direction.　The　effective　Young＇s　modulus　is　formulated　by　the　modified　Halpin-Tsai　model.　The　rule　of　mixture　is　applied　to　calculate　the　effective　Poisson＇s　ratio　and　mass　density.　The　equations　of　motion　are　established　by　using　the　first-order　shear　deformation　theory　and　von　Karman　geometric　nonlinear　theory.　Based　on　the　Rayleigh-Ritz　method,　the　natural　frequencies　of　the　rotating　FG　blade　reinforced　with　the　GPLs　are　obtained.　The　accuracy　of　the　present　method　is　verified　by　comparing　the　obtained　results　with　those　of　the　finite　element　method　and　published　literature.　A　comprehensive　parametric　study　is　conducted,　with　a　particular　focus　on　the　effects　of　distribution　pattern,　weight　fraction,　and　geometries　size　of　the　GPLs　together　with　dimensional　parameters　of　varying　cross-sections　blade　on　the　dynamics　of　the　FG　blades　reinforced　with　the　GPLs.