The invention belongs to the technical field of sky railway vertical column foundations, and particularly relates to a sky railway vertical column foundation with less excavation and a powerful structure and a construction method of the foundation. The sky railway vertical column foundation includes a base prepared by precast caisson pouring and a sky railway vertical column detachably and fixedlyarranged on the base; perforations with array distribution are formed in the side wall of a precast caisson, a plurality of reinforcement devices are further arranged on the side wall of the precastcaisson, wherein the reinforcement devices are inserted into the surrounding soil foundation from the interior of the precast caisson through the perforations, and each reinforcement device is of a tubular structure with the empty center; and the bottom of each reinforcement device is in a conical shape, and a plurality of wall holes with the array distribution are formed in tubular side wall between the upper part and the bottom of each reinforcement device. The sky railway vertical column foundation has the advantages of being small in footprint, powerful in structure, safety and reliability, and meanwhile, can be used for various construction foundation such as cross-sitting types, suspension types, railway bridges, building structures and highways.