An apparatus for preventing bedsores is disclosed. The apparatus includes a sub-frame, a main frame, a right arm lifting unit, a left leg lifting unit, a side block lifting unit, and a sub-frame tilting unit. The sub-frame includes a center block and a central shaft. The main frame surrounds and supports the sub-frame. The right arm lifting unit is supported by the sub-frame below the right arm lifting block. The left leg lifting unit is supported below the left leg lifting block by the sub-frame. The side block lifting unit is supported below the right block by the sub-frame. The sub-frame tilting unit includes a first gear, a second gear, a chain, and a first gear driving motor.
