The suspension thrust bearing device for a motor vehicle comprises a rolling bearing (22) forming a thrust and provided with an upper ring, a lower ring, and at least one row of rolling elements placed between the rings, a bearing cap (18) in contact with the upper ring, and a supporting cap (20) in contact with the lower ring and forming a bearing means for a suspension spring (12). At least one of the said caps comprises a body formed of at least a first synthetic material and an insert (34) at least partly covered by the said body. The said insert is formed of at least a second synthetic material different from the first synthetic material.