PURPOSE: To prevent deterioration of space efficiency around a leaf spring with ease of operation ensured by understeering vehicle turning characteristics.

CONSTITUTION: Both leaf springs 11, 11 extending in the longitudinal direction of a vehicle body are disposed parallel to each other, and an axle case 19 is supported at the central position of both the leaf springs 11, 11 through U bolts 15, 16. The front ends 11a, 11a of both the leaf springs 11, 11 are mounted onto the vehicle body with right and left vibration insulators 12, 32 constituted of double structure of horizontal vibration insulating bushes 23, 24. Respective brackets 21, 21, 22, 22 of right and left vibration insulating bodies 12, 12 are bent into a crank shape, and respective front ends 21b, 21b, 22b, 22b are formed into a flaring shape in the vehicle body forward direction.