Free　vibration　and　static　bending　of　functionally　graded　(FG)　graphene　nanoplatelet　(GPL)　reinforced　composite　doubly-curved　shallow　shells　with　three　distinguished　distributions　are　analyzed.　Material　properties　with　gradient　variation　in　the　thickness　aspect　are　evaluated　by　the　modified　Halpin-Tsai　model.　Mathematical　model　of　the　simply　supported　doubly-curved　shallow　shells　rests　upon　Hamilton　Principle　and　a　higher　order　shear　deformation　theory　(HSDT).　The　free　vibration　frequencies　and　bending　deflections　are　gained　by　taking　into　account　Navier　technique.　The　agreement　between　the　obtained　results　and　ANSYS　as　well　as　the　prior　results　in　the　open　literature　verifies　the　accuracy　of　the　theory　in　this　article.　Further,　parametric　studies　are　accomplished　to　highlight　the　significant　influence　of　GPL　distribution　patterns　and　weight　fraction,　stratification　number,　dimensions　of　GPLs　and　shells　on　the　mechanical　behavior　of　the　system.　(C)　2018　The　Author.　Published　by　Elsevier　B.V.