The Xiangshan Bridge under construction is a semi-floating cable-stayed bridge with double pylons, double cable planes, and double-deck steel truss girders. The pylons are herringbone-shaped, with only corbels at the beam bottom and no crossbeams. The axis of the pylon limb is 9.9° to the plumb line, and the cantilever length is 165.8 m. The cantilever length of the inclined pylon limb is rare. In addition to ensuring the safety of pylon construction, reasonable design schemes of temporary lateral bracings should also facilitate the construction of pylons and temporary lateral bracings and save the investment of temporary lateral bracings. In view of the shortcomings of setting too many active lateral bracings (increasing unnecessary measures and costs) caused by the traditional force safety principle, such as “the horizontal displacement of the inclined pylon limb does not exceed the allowable deviation of the axis, and the stress of the pylon limb does not exceed the standard”, a new simplified force safety principle that “the stress of the pylon limb does not exceed the standard” was adopted. Through the simulation calculation of each pylon construction stage by the finite element software Midas Civil, combined with the structural characteristics of the Xiangshan Bridge pylon and the hydrological and meteorological conditions of the bridge site, the design scheme of the temporary lateral bracings position, section size, active force size, and demolition sequence for the Xiangshan Bridge pylon was determined. The number of temporary lateral bracings in the obtained design scheme was small, and only one layer of active bracings was set. By using the obtained design scheme for lateral bracings, the construction of the pylon is smooth (it is about to cap), and no cracks are generated. The axis deviation of the pylon is within the allowable range of the design.