The invention discloses an assembling method for a rush-repair tower section. Two sets of independent equipment including a stand column welding cutter and a transverse and vertical plate welding cutter are adopted, the tower section is welded and fixed step by step, operation is easier, and assembling is more convenient. Moreover, the connection among formed parts is reliable, so that the tower section has higher strength and can be dragged on the ground at will, and the situations of scattering, falling of the parts and the like are avoided. The method has the advantages of high precision, high efficiency and high strength.