The present invention relates to a suspension bearing device, comprising a rolling bearing forming an axial stop along a main axis and at least one seal adapted for protecting the rolling bearing from ingress of water or of polluting particles. The device is characterized in that it also comprises a bottom cup and a top cup made of plastic, in contact with the rolling bearing, the bottom cup forming a bearing means for a suspension spring, and in that the or each seal is made of thermoplastic overmolded onto a first element between the cups and comprises a base of substantially annular shape from which extends at least one sealing lip in contact with the second element between the cups. The invention also relates to a strut of a motor vehicle, comprising a damper and a suspension bearing device as mentioned above.