The invention discloses a positioning device for CT-guided puncture, which comprises a supporting column, wherein a fixed base is arranged at the lower end of the supporting column, a guide rod is arranged at the lower end of the side surface of the supporting column, a connecting member is arranged on the upper end of the supporting column, the supporting column is rotatably connected with the connecting member through an adjusting bolt, a telescopic rod is arranged on the side surface of the connecting member, the connecting member is connected with the fixed end of the telescopic rod, a first fastening knob is arranged on the side surface of the fixed end of the telescopic rod, the telescopic end of the telescopic rod is provided with a positioning device, the telescopic end of the telescopic rod and the outer sleeve of the positioning device are movably connected in a clamping mode, the side surface of the outer sleeve is provided with a second scale line, the side surface of the telescopic end of the telescopic rod is provided with an indicator plate, and the upper end of the positioning device is provided with a positioning test device. The positioning device for CT-guided puncture has a simple structure, is adjustable, can test and accurately position the puncture site, reduces the damage to patients, improves the work efficiency, saves time, and is convenient to use.