Crossed Roller Bearing is mainly consisted of an outer ring, an inner ring, a plurality of rollers and a plurality of spacers. The roller lies between the inner ring and the outer ring. The spacer is placed between rollers to prevent the mutual friction between rollers so as to decrease the torque resistance for rotation. In addition, the surface of the roller and the rolling track is linear contact. So, when the bearing is loaded, the loading area will be very large.