The invention discloses a high-precision positioning puncture mechanism for CT puncture guiding. The high-precision positioning puncture mechanism comprises a connecting cavity, a third rotating shaft, a fourth rotating shaft, a worm, a worm gear, a rack, a rotating part, a bilateral rack, a clamping plate, a first rotating rod and a second rotating rod. The device can replace manual work to accurately position a marked part in actual use, so that a puncture needle can directly face the marked part through self-adjustment, positioning is more accurate, the puncture depth can be better controlled, sampling safety and accuracy are guaranteed, the labor intensity of medical staff is reduced, and high practicability is achieved; the upper part of the puncture needle can be sealed while the puncture needle is fixed through the linkage mechanism, so that the puncture needle is in a sealed state in an actual puncture process, sterile sampling is ensured, subsequent cleaning is convenient, and the overall operation is convenient. The problem that sampling errors or errors are caused due to the fact that the puncture position is still prone to deviation when a diagnosis and treatment physician conducts puncture sampling manually is solved.