A tunable absorber,composed of a graphene ribbon on two layers of TiO2-Au between two slabs of dielectric material all on a metal substrate,is designed and numerically investigated.The absorption of the composite structure varies with the geometrical parameters of the structure and the physical parameters of graphene at mid-infrared frequencies.The numerical simulation shows that a near-perfect absorption with single and dual bands can be achieved in a certain frequency range.We also analyze the electric and surface current distributions to study the dual-band absorber.The results show that the absorber can be tuned by the chemical potential and electron-phonon relaxation time of graphene,and electromagnetically induced transparency phenomenon can be obtained.The results of this study may be beneficial in the fields of infrared communication,perfect absorbers,sensors and filters.