The invention provides a machining machine and a machining process for manufacturing a steel pipe structure of a steel pipe truss. The machining machine comprises a workbench, a supporting and limiting device and a bending device. According to the device, the following problems existing in the machining process of manufacturing the steel pipe structure of the steel pipe truss can be solved of a, bending machining can only be carried out for a certain size when traditional steel pipes are bent at present, bending machining cannot be carried out on the steel pipes of various sizes, meanwhile when traditional bending equipment is used for bending the steel pipes, steel pipes with different angles cannot be machined, only one bending angle can be achieved, the function is single, and the effect is limited; and b, when the existing bending equipment is used for bending, the bending part of the steel pipe is sunken and deformed, repairing is often needed, time and labor are wasted, even some steel pipes are directly scrapped, the cost is increased, meanwhile, certain resilience exists after the steel pipe is bent, so that the bending angle of the finally formed steel pipe does not meet the requirement, and the steel pipe needs to be processed again.