The invention provides a pipe bending technology of an ultra-large type intelligent vertical hydraulic cold pipe bending machine. The technology is characterized by comprising following steps: the ultra-large type intelligent vertical hydraulic cold pipe bending machine is assembled, and comprises a machine body main frame, an upper tire, a lower tire, a clamping tire and a drive mechanism, wherein the upper tire, the lower tire, the clamping tire and the drive mechanism are arranged on the machine body main frame; a crane is used for enabling the pipe bending machine to be close to an upper pipe at the end of the clamping tire, and a steel pipe is pulled to the initial pipe bending position; the double-curved face of the tire above a steel pipe serves as an upper supporting point, the clamping tire serves as the lower supporting point, under lifting of a lower tire bending cylinder, the steel pipe begins to bend and deform, and when a bending oil cylinder rises to the set height, and the steel pipe reaches the set bending angle, jacking is stopped. On the premise that the strength of the steel pipe is not affected, the steel pipe is bent to have different curvatures with the curvature radius larger than or equal to 40D on the construction site, operation is convenient, use is reliable, work efficiency is obviously improved, and labor intensity is reduced.