The invention relates to a bolted-connection-free high voltage doubling cylinder which comprises a first voltage doubling cylinder unit and a second voltage doubling cylinder unit. The side face of one end of the first voltage doubling cylinder unit is provided with a locking groove, the second voltage doubling cylinder unit is provided with a locking device matched with the locking groove, the locking device is arranged on the side face of the connecting end of the second voltage doubling cylinder unit and the first voltage doubling cylinder unit through a first rotating shaft, and the firstvoltage doubling cylinder unit and the second voltage doubling cylinder unit are mutually locked by the locking groove and the locking device. According to the bolted-connection-free high voltage doubling cylinder, the units are connected completely without any bolts and screw holes, the voltage doubling cylinder units are fixedly connected only by the aid of the locking device between the voltagedoubling cylinder units, the locking device is organically combined with a voltage doubling cylinder equalizing ring, electric field distribution of the voltage doubling cylinder is slightly affected, the connecting and detaching process of the voltage doubling cylinder units is quite simple and effective, a variety of inconvenience caused by bolted connection is completely avoided, and the working efficiency of high voltage electrical test is greatly improved.