To provide a damping force adjusting type cylinder device capable of reducing erroneous detection when detecting abnormality.

A damping force variable damper 6 is connected between a carriage 3 and a vehicle body 2. The damping force variable damper 6 is mounted with an actuator 7 for adjusting a damping force characteristic, and is incorporated with a force sensor 12 for detecting force acting on the vehicle body 2 from the damping force variable damper 6. An acceleration sensor 13 is arranged in the vehicle body 2, and detects vehicle body acceleration in the vertical direction. A control device 14 controls the damping force characteristic of the damping force variable damper 6 by using a detecting signal of the force sensor 12 and the acceleration sensor 13 when determining that the state is a normal state. On the other hand, the control device 14 controls the damping force characteristic of the damping force variable damper 6 by using the detecting signal of the acceleration sensor 13 without using the detecting signal from the force sensor 12 when determining that the state is a sensor failure state.