The invention provides a cable tower area beam section installing method. The cable tower area beam section installing method comprises the following steps that a cable tower area beam section is divided into 3-5 to-be-assembled beam sections by taking the axis where a lower tower column is located as the symmetrical axis according to the structure and the position; a transport ship loaded with atleast one to-be-assembled beam section is positioned and fixed relative to the lower tower column; a floating crane meeting the hoisting requirements stops on the outer side of the lower tower column; the front end and the back end of the floating crane are both anchored by adopting two first anchor cables which are arranged in a crossed manner and extend for the preset length in the horizontal direction, and the length that the first anchor cables extend in the horizontal direction is larger than that of the floating crane; and the to-be-assembled beam sections are sequentially hoisted to the top of the lower tower column from the transport ship by means of the floating crane. According to the cable tower area beam section installing method, the stability of the floating crane is enhanced through the mutual pulling action of the two first anchor cables which are arranged in a crossed manner at the front end and the back end of the floating crane, the first anchor cables extend for acertain length in the horizontal direction, the anchoring effect of the first anchor cables is further improved, and the hoisting construction stability is guaranteed.