Poly(3,4-ethylenedioxythiophene):　poly　(styrenesulfonate),　namely,　PEDOT:　PSS　or　PP　as　one　branch　of　conductive　polymers　(CPs)　which　can　effectively　transform　electrical　energy　to　mechanical　energy,　has　been　applied　in　many　fields　including　electrochemical　ionic　soft　actuators　(EISAs),　in　terms　of　its　high　conductivity　(0.1∼　3000　S/cm-1),　small　band　gap　(1.6–1.7　eV),　low　redox　potential,　good　durability,　good　chemical　and　thermal　stability,　excellent　mechanical　properties,　and　adjustability.　Furthermore,　when　PP　as　active　binders　are　mixed　with　nanomaterials,　they　can　not　only　be　used　to　disperse　nanomaterials　and　prevent　their　aggregation,　but　also　efficiently　enhance　mutual　conduction,　specific　surface　aera,　and　redox　activity.　Here,　an　extensive　review　on　PP-based　EISAs　including　PP-carbon　nanomaterials　and　PP-non　carbon　nanomaterials　is　reported,　highlighting　their　structure　and　fabrication,　electrochemical　properties,　actuation　performance,　mechanical　properties,　and　applications.　The　great　synergy　between　PP　and　advanced　nanomaterials　with　diverse　fabricating　principles　that　provide　sufficient　ions　storage　space,　ordered　charges　pathways,　stiffness　for　high　actuation　displacement,　fast　responds　and　excellent　flexibility　is　emphasized.　Furthermore,　the　novel　applications　of　EISAs　toward　smart　devices　and　soft　robots　are　also　summarized.　Finally,　the　review　also　proposed　the　current　challenges　and　further　prospect　of　EISAs.　©　2023　Elsevier　B.V.