Ball/roller combination slewing bearing is composed of outer seat-ring, inner seat-ring, ball and roller. The rollers and balls are respectively on a horizontal line rollway of outer seat-ring and global rollway of inner seat-ring. The rollers load the axial moment and the balls load the radial moment, while both of them load the torque moment. So ball/roller combination slewing bearing can not only load axial moment, but also certain torque moment and radial moment. The advantages of small size of section and low cost is very obvious and better applied on large Engineering Mechanical Equipments.