The invention discloses a height adjusting mechanism for electric cabinet pipe edge preparation. The mechanism comprises a base plate, wherein a lifting cylinder and a guide rod are installed on the base plate, a lead screw is arranged in the lifting cylinder, the upper end of the lead screw is sleeved with a lifting table, a spiral gear is installed at the lower end of the lead screw, a blind hole is formed in the bottom of the lifting table, a nut is installed in the blind hole, the upper end of the lead screw penetrates through the nut, a through hole is formed in the lifting table, and the guide rod penetrates through the through hole. The mechanism further comprises a motor, wherein a bevel gear is connected to the output end of the motor and penetrates through the lifting cylinder to be matched with the spiral gear. When acting force is applied to the lifting table, stress balance of the whole lifting table in the horizontal direction can be kept through the guide rod, damage to internal components of the lifting cylinder caused by local stress concentration of the lifting table is avoided, and then the position where the output end of the motor is connected with the lifting cylinder is better protected and a cutting tool is better stabilized and supported by the lifting table.