The Wujiang Grand Bridge is a deck concrete filled steel tube arch bridge with the calculated span of 475 m. The construction technology of cable hoisting and cable-stayed buckling is adopted. By utilizing the base slab of pile foundation of approach bridge as the anchorage of anchor cable， the permanent and temporary combination is cleverly realized by the buckling system. A calculation method for the horizontal load-bearing capacity of the base slab anchorage and the precise positioning coordinates for the cableway through the pier is proposed. Based on this method,the key construction technical essentials for base slab anchorage of the permanent and temporary combined pile foundation are discussed in detail. The results demonstrate that in the cantilever assemble construction of long-span concrete filled steel tube arch bridge in the mountainous area, the use of base slab of pile foundation of approach bridge as the anchorage of anchor cable is safe and reliable for the structures, and compared with the single construction of anchorage, it will greatly save the construction cost and shorten the construction period, which can provide the reference for the similar projects.