One　of　the　central　challenges　in　realizing　multiferroics-based　magnetoelectric　memories　is　to　switch　perpendicular　magnetic　anisotropy　(PMA)　with　a　control　voltage.　In　this　study,　we　demonstrate　electrical　flipping　of　magnetization　between　the　out-of-plane　and　the　in-plane　directions　in　(Co/Pt)(3)/(011)　Pb(Mg1/3Nb2/3)O-3-PbTiO3　multiferroic　heterostructures　through　a　voltage-controllable　spin　reorientation　transition　(SRT).　The　SRT　onset　temperature　can　be　dramatically　suppressed　at　least　200　K　by　applying　an　electric　field,　accompanied　by　a　giant　electric-field-induced　effective　magnetic　anisotropy　field　(Delta　H-eff)　up　to　1100　Oe　at　100　K.　In　comparison　with　conventional　strain-mediated　magnetoelastic　coupling　that　provides　a　Delta　H-eff　of　only　110　Oe,　that　enormous　effective　field　is　mainly　related　to　the　interface　effect　of　electric　field　modification　of　spin　orbit　coupling　from　Co/Pt　interfacial　hybridization　via　strain.　Moreover,　electric　field　control　of　SRT　is　also　achieved　at　room　temperature,　resulting　in　a　Delta　H-eff　of　nearly　550　Oe.　In　addition,　ferroelastically　nonvolatile　switching　of　PMA　has　been　demonstrated　in　this　system.　E-field　control　of　PMA　and　SRT　in　multiferroic　heterostructures　not　only　provides　a　platform　to　study　strain　effect　and　interfacial　effect　on　magnetic　anisotropy　of　the　ultrathin　ferromagnetic　films　but　also　enables　the　realization　of　power　efficient　PMA　magnetoelectric　and　spintronic　devices.