A　giant　field-induced　strain　of　0.65%　with　excellent　temperature　insensitivity　and　fatigue　resistance　was　achieved　by　introducing　1.5　mol.%　B-site　complex　cations　(Zn1/3Nb2/3)(4+)　into　the　0.93(Bi1/2Na　1/2)TiO3-0.07BaTiO(3)　lead-free　ferroelectric　ceramics.　(Bi1/2Na1/2)(0.93)Ba-0.07(Zn1/3Nb2/3)(x)Tit-xO(3)　(0　＜=　x　＜=　0.025)　ceramics　were　prepared　by　the　columbite　route,　their　microstructure,　electric　properties,　and　field-induced　strain　behavior　were　systematically　investigated.　XRD　analysis　reveals　that　the　B-site　substitution　by　complex　cations　(Zn1/3Nb2/3)(4+)　induces　the　phase　transition　from　R3c　to　pseudocubic　structures,　and　demonstrates　different　phase　evolution　under　field　applied.　At　the　composition　x=　0.015,　a　composition-driven　boundary　between　the　nonergodic　state　and　ergodic　state　is　observed.　Meanwhile,　the　substitution　by　complex　cations　(Zn1/3Nb2/3　)(4+)　reduces　the　dimension　of　polar　nanoregions　(PNRs)　due　to　the　destruction　of　the　long-range　ferroelectric　ordering.　A　phenomenological　illustration　based　on　Bokov＇s　suggestion　and　Landau-Devenshire　theory　suggests　the　relationship　between　the　size　of　PNRs　and　field-induced　strain　behavior.　(C)　2018　Elsevier　B.V.　All　rights　reserved.