The invention discloses a thin oil lubrication sealing device for a vacuum roller liner bearing. The bearing is arranged between a liner and a transmission-side shaft head, and a bearing seat is fixedon the transmission-side shaft head; the bearing is fixedly sleeved on a shaft sleeve which is tightly fixed to a liner shaft and tightly fixed by locking nuts; the bearing is arranged in the bearingseat, a bearing cover is fixed on one end surface of the bearing seat and can close one end of a liner shaft; and one end surface of the inner bearing cover is fixed on the other end surface of the bearing seat. The invention realizes the thin oil lubrication sealing of the bearing by mechanical seal in a flaring chamber, oil seal, labyrinth seal and grease seal, is easy to add oil, hardly leaksthin oil, is suitable for the vacuum roller bearing of a papermaking machine at medium and high speeds and prolongs the service life of the bearing.