Abstract: Ionic crystals usually possess high dielectric constant. The charged particle is able to induce dielec- tric polarization in crystal,which functions as a charge-trapping potential well. The polarons and bipolarons are able to form when their trapping states in potential well are stable. In this paper, a simplified method is utilized and the crystal is regarded as isotropic and uniform media. By using the picture of classical physics and model of quantum harmonic oscillator, the ground state energies of polarons and hipolarons are calculated,and some theoretical analy- sis is given.

Key words: ionic crystal, polaron, bipolaron