Rhombohedral　La:BiFeO3　films　were　successfully　prepared　on　Si　substrates　by　using　Radio　frequency　magnetron　sputtering　method.　The　LaNiO3　as　buffer　layer　is　beneficial　for　improving　the　quality　of　the　film,　reducing　surface　roughness,　and　getting　rid　of　the　impure　phase.　The　Bi0.9La0.1FeO3/LaNiO3/Si　film　has　the　largest　piezoelectric　coefficient　with　d(33)　reaching　4.76　pm/V,　which　is　about　2.5　times　larger　than　that　of　BiFeO3/LaNiO3/Si.　The　saturation　magnetization　and　the　MCD　signal　of　BiFeO3　films　are　significantly　enhanced　by　doping　La3+.　The　MCD　ellipticity　of　La:BiFeO3　film　at　555　nm　increase　with　the　increase　of　La3+　concentration.　Bi0.7La0.3FeO3/　LaNiO3/Si　film　show　strong　magneto-optical　effect　with　the　high　MCD　ellipticity　of　850　deg./cm,　which　is　more　than　about　1.7　times　larger　than　that　of　BiFeO3　film.　This　film　is　expected　to　be　developed　into　a　new　multifunctional　material　with　multi-field　coupling　of　electro-opt-magnetism.