The utility model provides a little non -contact fingertip sealing device of leakage rate under fluid dynamic pressure and sealability, the stopped status has under the running state to it is big notenough to overcome poor leakage rate height that results in of fingertip sealed " hesitation effect " and rotor precession adaptability or wearing and tearing volume, and it is by backplate, low pressure finger point gasket and take the high pressure finger point roof beam and the rotor of fingertip boots to form, taking the high pressure finger point roof beam of fingertip boots, low pressure finger point gasket, backplate to stack in proper order from high pressure to low pressure and being in the same place through rivet connection, form the ring, the overcoat is on the rotor, the fingertipboots constitute the seal interface with the rotor, be provided with drainage hole and interior annular on the fingertip boots, the surface parts processing of rotor has spiral shell hand groove, thedrainage hole communicates with each other with interior annular, and spiral shell hand groove is relative in radial orientation with interior annular, when the rotor rotated, the fluid of high -pressure side formed the fluid dynamic pressure through drainage hole, interior annular, spiral shell hand groove pump sending to seal interface, pushes the fingertip boots open, has avoided the frictionand wear between fingertip and rotor.