Bearing unit which combines rolling bearing with the bearing block. Most pillow block bearings make the external diameter spherical and are mounted with bearing block with a spherical inner hole. The product has a variety of structural forms and good versatility and interchangeability. Meanwhile, bearing unit has adjustable disposition and a double structure sealing device, and it is easy to install and can work under bad environment. The bearing block generally adopts the casting forming. Common bearing blocks consist of P vertical seat, F square base, FS convex square seat, FC convex circular seat, FL diamond-shaped seat. Our products apply to the situations which give priority to have simple equipment and spare parts, such as agricultural machinery, transport system or building machinery.