A front fork comprises a telescopic tube ( 1, 32 ) in which a damper cylinder ( 3 ) generates a damping force. The damper cylinder ( 3 ) comprises a guide sleeve ( 4 ) and a free piston ( 6 ) having an inner circumference which slides on the outer circumference of the guide sleeve ( 4 ) and an outer circumference which slides on the inner circumference of the damper cylinder ( 3 ). A lateral through-hole ( 11 ) formed in the guide sleeve ( 4 ) connects an auxiliary reservoir (R 3 ) formed outside the damper cylinder ( 3 ) and an oil reservoir (R 2 ) via a flow path ( 12 ) formed in the guide sleeve ( 4 ) according to the displacement position of the free piston ( 6 ), thereby reducing the number of seal members required to be fitted on the outer circumference of the free piston ( 6 ) and enabling the free piston ( 6 ) to slide smoothly even when the telescopic tube ( 1, 32 ) suffers a bending force.