Active constrained layer damping (ACLD) is an activedamping form that replaces the uncontrolled constrained layer ofpassive constrained layer by controlled piezoelectric materials and actively controls the shear deformation of viscoelastic materials by controlled constrained layer in order to enhance the energy dissipation of vibration. It sufficiently combines the advantages of active control and passive damping and reveals excellent application values on structure vibration control. This paper explains the structure and the operating mechanism of ACLD at first. And then, reviews the recent researching progresses on structure modeling, control strategy and structure optimization of ACLD etc. At last, indicates the future application and summarizes the further studying problems.