Conductive　hydrogels　(CHs)　for　flexible　bioelectronic　devices　have　raised　great　attention　due　to　their　tunable　mechanical　performances,　adhesion,　anti-swelling,　and　biocompatibility.　This　review　summarizes　the　current　development　of　conductive　hydrogel-based　flexible　bioelectronic　devices　in　the　aspect　of　classifications　and　applications.　Firstly,　the　conductive　hydrogels　are　classified　into　two　kinds　according　to　the　types　of　conductivity:　ionic　conductive　hydrogels　and　electronic　conductive　hydrogels　(hydrogel　based　on　pure　conductive　materials,　introducing　conductive　micro/nano-materials).　Secondly,　the　applications　of　conductive　hydrogels　for　bioelectronic　device,　like　wearable　devices　(strain　sensor,　body　fluid　detector,　serviced　in　extreme　environment),　tissue　engineering　(skin,　heart,　nerve,　muscle),　and　other　applications　(bionic　robot,　cancer　treatment),　are　highly　illustrated.　Finally,　a　depth　outlook　is　given,　which　aims　to　promote　the　development　of　this　field　in　the　future.　This　work　reviews　the　recent　progress　of　conductive　hydrogels　for　bioelectronic　devices　from　the　aspect　of　classifications　and　typical　applications.　Furthermore,　the　current　challenges　and　the　corresponding　strategies　for　the　future　development　are　in-depth　discussed,　aiming　to　promote　the　practical　application　of　conductive　hydrogels　in　the　fields　of　biomedicine　and　clinical　medicine.image