The invention relates to a novel combined screwdriver. The upper end part of a screwdriver rod is closely matched with and inserted into a screwdriver-handle lower cylinder body at the lower end part of a screwdriver handle. The lower end of the screwdriver rod is provided with a screwdriver opening for turning a screw. A magnetic block is arranged in the screwdriver-handle lower cylinder body. The lower end of the screwdriver rod is provided with a screw tightening clamp which can tightly clamp a screw and move upwards and downwards along the screwdriver rod. A screwdriver-handle force adding arm part is closely matched with and movably sheathed with a rotary force adding arm. The middle of the upper part of the screwdriver handle is provided with a screwdriver-handle upper cylinder body A and a screwdriver-handle upper cylinder body B which both can be used for storing the rotary force adding arm and the screwdriver rod. The upper end part of the screwdriver handle is provided with an end cover which can be rotatably arranged at the upper end part of the screwdriver handle. When being used for turning the screw, the screwdriver is safe and labor-saving. When the screwdriver turns the screw, the screw does not incline, a notch at the top of the screw is not easily damaged, and the screwdriver can not slide out of the notch at the top of the screw or hurt the hand or other components. The screwdriver is convenient to be carried and has two purposes.