Abstract:In this paper,the properties of internal excited state of the strong coupling two dimensional magnetopolaron are studied.The energy of the first internal excited state and the vibration freguency of the magnetopolaron were calculated by using the linear combination operator and the unitary transformation methods.Two limiting cases are discussed.The numerical results of AgCl crystal show that the first internal excited state energy and the vibration freguency of the megnetopolaron will increase with increasing the magnetic field.