To provide a suspension cylinder device to generate damping force by driving force of an actuator, capable of coping with failure of the actuator.

This suspension cylinder device 10 devised to expand and contract in correspondence with relative movement of a part of a car body and a wheel and to give resistance against expansion and contraction to a motor 32 is furnished with a frictional resistance generating mechanism 60 to generate frictional resistance against expansion and contraction at the time of defection of the motor 32. The frictional resistance generating mechanism 60 , for example, installs a sliding ring 70 arranged on a cylinder 22 in a state of contracting a diameter on a rod 24 at the time of defection of the motor 32 and generates frictional resistance against sliding by making a state of sliding on an inner peripheral surface 74 of the cylinder 22 in the case when the cylinder 22 and the rod 24 relatively move in the axial direction. That is, expansion and contraction of the suspension cylinder device 10 becomes expansion and contraction against the frictional resistance and it is possible to generate the damping force at the time of failure of the motor 32.