PURPOSE: To improve riding quality by setting up a spring member, pressing a strut in the car width direction, in space between the vicinity of a lower end of the strut, in a strut type suspension.

CONSTITUTION: A lower end of a hydropneumatic type expansion strut 10 is fixed to an upper arm 12a of a tire support member 12, making it tilt to the center side of a vehicle, and it is set up after supporting the upper end on an upper mount 14 provided with a fluid port 13. Then, a spring member 19 consisting of a gas spring is installed in space between a tip of the upper arm 12a of the tire support member 12 and a bush 20 locked to a car body 17 in the width direction in making the side of a bracket 20 higher and slidably. With this constitution, frictional force in a strut sliding part is abated by dint of lateral force being imposed on a strut upper end, thus the extent of riding quality can be improved.