The invention discloses a device for constructing a dilator channel under a unilateral pedicle admission passage condition. The device for constructing the dilator channel under the unilateral pedicle admission passage condition comprises a work catheter, a guiding device and a kirschner wire. The work catheter is a hollow tube, and one end of the work catheter is provided with a handle I. The guiding device is arranged in the work catheter and is a hollow tube. The kirschner wire is arranged in the guiding device. One end of the guiding device is provided with a guiding output opening. The guiding output opening is an open-type fan-shaped opening in a circular arc shape. The other end of the guiding device is provided with a direction mark, and the position of the direction mark is consistent with the opening direction of the guiding output opening. The device for constructing the dilator channel under the unilateral pedicle admission passage condition is simple in structure, convenient to operate and applicable to industrial production. The problems that in existing unilateral pedicle puncture surgery, it is difficult for the kirschner wire to enter vertebral body on the opposite side, the vertebral body wall is pierced easily, the inserting depth is insufficient and the bone cement diffusion effect is poor are solved, the dilator channel can be constructed on the opposite side of the admission passage vertebral body safely and accurately under the unilateral pedicle admission passage condition, so that the bilateral pedicle admission passage surgical scheme mostly used at present is expected to be replaced, and the more minimally invasive purpose is achieved.