The invention discloses an assembled wire stringing construction method in a crossed isolated high-speed rail, and relates to an assembled wire stringing construction method. The assembled wire stringing construction method comprises the following steps of 1) calculating suspension length between two wire hanging points according to sag stipulated by design, and calculating the length of a brokenline; 2) tensioning and stretching a guide ground wire on ground, and cutting the guide ground wire after the guide ground wire is measured; 3) crimping a tension wire clamp, installing the tension wire clamp onto a fitting string, and slightly adjusting the sag; and 4) performing traction crossing operation on the guide ground wire after a night rail maintenance window is opened, and performing wire hanging and accessory installation of the guide ground wire. According to the assembled wire stringing construction method disclosed by the technical scheme, the traditional stringing process stepcan be cancelled, the crimping process can be completed at daytime, the operation time at night is greatly reduced, and the wire stringing construction efficiency at night is improved.