In　this　paper,　the　transfer　matrix　symplectic　conserved　perturbation　method　for　LC　circuit　with　nonlinear　capacitor　is　studied.　Deducing　from　the　Coulomb　volt　characteristics　of　the　nonlinear　capacitance,　electric　charge　q　of　the　capacitor　and　the　magnetic　flux　linkage.　of　the　inductance　is　treated　as　the　state　variables　and　the　corresponding　control　equations　are　discribed　in　dual　form.　The　Hamiltonian　matrix　is　written　as　the　combination　of　linear　and　nonlinear　parts.　On　the　basis　of　the　analytical　solution　of　the　linear　part,　the　problem　could　be　considered　as　symplectic　matrix　multiplication　by　using　canonical　transformation.　After　obtaining　the　solution　of　the　corresponding　part.　The　characteristics　of　the　LC　circuit　oscillation　can　be　solved.　The　numerical　results　reveal　that　higher　precision　and　stability　could　be　acheived　by　utilizing　the　methed　proposed.