Provided is a method for processing and manufacturing a metal structural material by knitting metal wires into metal screen mesh strips, tightly coiling the metal screen mesh strips to form a coiled blank body which is coated layer-by-layer and in which an outer-layer material tightly covers an inner-layer material; sintering the coiled blank body; reducing gaps within the coiled blank body material by plastic processing to reach a porosity that fulfills requirements, and manufacturing mechanical structural parts therefrom.