The invention discloses a multi-point type steel strand single-piece pre-tightening device which is provided with a plurality of pre-tightening jacks, wherein oil cylinders of the pre-tightening jacks are fixed by a fastener assembly to form structures with the front and rear ends flush with each other; a bidirectional piston of each oil cylinder is a piston with a through hole, so that a steel strand can pass through a running-through structure where the inner hole of each bidirectional piston passes; the multiple bidirectional pistons are connected to form structures which move towards the same direction; the fastener assembly comprises an upper pressing plate and a lower pressing plate; the front ends of the oil cylinders of the pre-tightening jacks are connected with the inner side of the upper pressing plate, the rear ends of the oil cylinders of the pre-tightening jacks are connected with the inner side of the lower pressing plate; screw rods are arranged between the upper pressing plate and the lower pressing plate, and enable the upper pressing plate, the lower pressing plate and the oil cylinders to be fastened integrally. The multi-point type steel strand single-piece pre-tightening device has the advantages that a function of simultaneously and independently pre-tightening a plurality of prestressed bars is realized, the construction is convenient, the efficiency is high, and the labor intensity of a worker is low; the pre-tightening force on each prestressed bar is easy and uniform to control; the pre-tightening jacks are small in structure, light in weight, small in working space and convenient to mount and use.