Abstract: A leaf spring of plastic material having a spring body of fiber-reinforced plastic material, which at least at one end is provided with a thickening, with an end zone (1) of the spring body increasing in its thickness towards the spring end (5'). On this thickened end zone (1), a spring eye body (6, 19, 26) is wedged up at its appropriately laminar mounting zones with the aid of clamping sleeves.For the manufacture of the plastic material leaf spring, one advantageously starts with a spring body, the end zone (1) of which exhibits plane parallel top and bottom sides (2, 3), respectively, on which coatings of a plastic mass of fiber-reinforced duromer plastic material are applied to form the aforementioned thickening.