Abstract: The polaron ground state in asymmetric double heterostructure (ADHS) is studied. Using perturbation method, the binding energy and effective mass of a polaron are calculated and expressed as the functions of the width of the center layer. In considering electron-phonon interactions, both the confined longitudinal optical modes and the interface phonon modes are included. The results differ largely fromwhat is in symmetric double heterostructure (DHS), for the contribution of the interface phonons is larger and wider than in DHS, showing that the asymmetry in structure has a profound effect on the properties of ADHS.