The spherical roller bearing has a double row of rollers. The outer ring has a common spherical raceway, and the inner ring has two raceways and is tilted at an Angle relative to the bearing axis. This kind of ingenious construction makes it self-aligning, so it is not easy to be affected by the Angle of the shaft and bearing box on the error or bending of the shaft. It is suitable for the occasion of the error caused by the installation error or deflection of the shaft. The bearing can bear radial load as well as bi-directional axial load.