Abstract: The present application relates to the technical field of directional drill rod assembly, and discloses methods for mounting and testing a central communication cable assembly of a directional drill rod, the mounting method including: according to drawing requirements, mounting an O-shaped sealing member in a sealing groove of an insulating male connector, an insulating female connector, a communication cable direct connector and a communication cable tapered connector, and processing, connecting, and mounting the various components. By means of the method, the central communication cable assembly of a directional drill rod is mounted, and the product quality stability is good.