Magnonics　or　spin　waves　have　the　potential　to　serve　as　the　carrier　for　future　information　communication.　A　controllable　spin　wave　resonance　(SWR)　device　is　demonstrated　in　a　Au/[DEME](+)[TFSI](-)/LSMO/STO　capacitor　heterostructure,　which　could　be　regulated　by　ionic　liquid　gating　(ILG)　method.　The　SWR　critical　angle　phi(C),　excitation　position　to　perform　uniform　precession,　is　shifted　in　a　reversible　manner　(thus　recording　＂off＂　and　＂on＂)　with　+1.5　V　gating　voltage　(V-g),　measured　by　quantitative　angular　dependent　electron　spin　resonance　(ESR)　spectroscopy.　Based　on　the　modified　Puszkarski＇s　surface　inhomogeneity　model,　the　ILG　control　SWR　at　low　V-g　(V-g　＜　1.5　V)　can　be　explained　by　a　charge-doping-induced　effective　surface　magnetic　anisotropy　change.　Applying　a　higher　V-g　(V-g　＞　1.5　V)　enhances　the　surface　mode　SWR　and　gradually　diminishes　the　body　mode　SWR.　Oxygen　vacancies　generate　at　higher　V-g　(V-g　＞　1.5　V)　resulting　in　the　modulation　of　superexchange　between　the　Mn　ions,　evidenced　by　X-ray　photoelectron　spectroscopy　and　secondary　ion　mass　spectroscopy　characterization.　This　ILG　control　SWR　presents　a　solution　for　energy　efficient　and　low-voltage　control　of　magnonics　and　spin　wave　devices.