A packaging substrate with fiat bumps for an electronic device and a method of manufacturing the same relate to the production of the packaging substrate for an electronic device, which comprises base islands and pins structurally and wherein the base islands and pins which all exhibit flat bump shape distribute on the front face of the substrate; the bottom side of the bumps, namely the rear faces of the base islands and pins are contiguous in the same substrate; in the packaging body of a single electronic device to be formed in later procedure, one or more base island may be included, the pins may arrange on one single side of the base island, also may arrange on the both sides or three sides of the base island, or may surround the base island so as to form the structure of one or more circuits of pins. The method includes that take a metal substrate is prepared, mask layers are adhered onto both sides of the metal substrate, the parts of the mask layers which need to be etched are removed, then half-etching is performed to form the recessed half-etching area, and then the residual mask layers on the metal substrate are removed to product the packaging substrate with flat bumps.