A damping force adjustment mechanism includes a casing that accommodates a working fluid, a seal member that divides an interior of the casing into a first fluid chamber and a second fluid chamber, a housing that holds the seal member and is accommodated in the casing, and adjusting a damping force of the working fluid in the housing, a damping valve accommodated in the housing, a first pilot chamber and a second pilot chamber formed in the housing, a control chamber formed in the housing, a control valve dividing an interior of the control chamber into first and second control chambers, an actuator configured to electrically drive and control the control valve, first and second communication passages, first and second stationary orifices respectively provided in the first and second communication passage, and a third stationary orifice provided in a third communication passage provided in the control valve.