With　the　increasing　demand　for　biomarker　detection　in　wearable　electronic　devices,　flexible　biosensors　have　garnered　significant　attention.　Additionally,　graphene　field-effect　transistors　(GFETs)　have　emerged　as　key　components　for　constructing　biosensors,　owing　to　their　high　sensitivity,　multifunctionality,　rapid　response,　and　low　cost.　Leveraging　the　advantages　of　flexible　substrates,　such　as　biocompatibility,　adaptability　to　complex　environments,　and　fabrication　flexibility,　flexible　GFET　sensors　exhibit　promising　prospects　in　detecting　various　biomarkers.　This　review　provides　a　concise　summary　of　design　strategies　for　flexible　GFET　biosensors,　including　non-encapsulated　gate　without　dielectric　layer　coverage　and　external　gate　designs.　Furthermore,　notable　advancements　in　sensing　applications　of　biomolecules,　such　as　proteins,　glucose,　and　ions,　are　highlighted.　Finally,　we　discuss　the　future　challenges　and　prospects　in　this　field,　aiming　to　inspire　researchers　to　address　these　issues　in　their　further　investigations.　Copyright　©　2023　Hu,　Sun,　Tian,　Mo,　Xie,　Song,　Zhang　and　Dong.