A sealing device including a first annular rotating shield, a second annular shield, fixed and arranged in front of the first shield for delimiting therebetween a first annular chamber and a sealing ring provided with at least a first and a second annular lips that extend axially and radially project from a flange portion of the second shield and towards a flange portion of the first shield, inside the annular chamber. At least one of the first and second lips cooperates with the flange portion of the first shield without touching it for defining a first dynamic labyrinth seal therewith. The first shield integrally supports a third annular lip that extends projecting from the first shield towards one of the first and second lips without touching it for defining a second dynamic labyrinth seal between the first and second shield and inside the annular chamber.