With the use of variational method of Pekar type, this paper studied the energy levels of magnetopolaron in quantum wire with strong electron-phonon interaction. The magnetopolaron binding energy in the ground state and in the excited state, as well as the resonance frequency of magnetopolaron were calculated. Their dependence on the cyclotron frequency and the confinement strength of quantum wire was depicted. The limiting case of bulk type and strict two-dimensional type was discussed.