The invention relates to a high-voltage switch, a knife switch and a conductive tube assembly. The high-voltage switch comprises a knife switch. The knife switch comprises a lower conductive tube anda pull rod. The pull rod is sleeved with a balance spring, a closing buffer spring and an opening buffer spring. The lower conductive tube is connected with a closing lower stop structure. The pull rod is connected with a closing upper stop structure. The closing buffer spring and at least one of the closing upper stop structure and the closing lower stop structure are arranged at an interval. Theinterval constitutes a closing air stroke. The lower conductive tube is connected with an opening upper stop structure. The pull rod is connected with an opening lower stop structure. The opening buffer spring and at least one of the opening upper stop structure and the opening lower stop structure are arranged at an interval, and the interval constitutes an opening air stroke. The closing bufferspring buffers the pull rod in the rear part of the closing, and the opening buffer spring buffers the action of the pull rod in the rear part of the pull rod to prevent the mechanism from shaking due to the impact, which improves the stability and reliability of product movement and prolong the service life of the mechanism.