The invention relates to a sealing device of turbine pressurizing compressor, which comprises a middle case, a sealing ring base, a retaining oil spray disc, a retaining bearing, and an oil baffle plate between the retaining oil spray disc and the middle case. Wherein, the oil baffle plate, the middle case and the retaining bearing can form a stable sealing chamber; the oil baffle plate is mounted at the inclined surface of annular heave to limit the flowing shape of machine oil with resisting and dividing the machine oil; the case of retaining oil spray disc that connecting the oil container has a annular heave whose inner and outer sides have inclined surface to change the flowing direction; the sealing ring base has a guide groove; the guide groove and the retaining oil spray disc form a guide channel to guide the machine oil leaked from the movable sealing gap between the oil baffle plate and the retaining oil spray disc into the oil reflux cut of middle case. The invention can effectively reduce the oil leakage with wider market prospect.