To provide a pneumatic suspension device which adjusts air pressure with a shock absorber using air, thereby improving the conformability to ride in a vehicle.

The present invention relates to a suspension device provided with a cylinder; a piston reciprocating inside the cylinder; and a piston rod coupled to the piston and protruding outward from the cylinder, and comprising a main spring attached to the inside of the cylinder to absorb an impact; a sensing means which senses the position and change amount of the piston; an air nozzle coupled to an actuator to feed air to the inside of the cylinder depending on the position and change amount of the piston; an air flow path which connects an upper end and a lower end of the cylinder to allow air in an upper space and an lower space of the piston to flow in communication with each other; and a solenoid valve which opens/ closes the air flow path.