Abstract: A low-carbon, low-alloy and high-formability dual-phase steel having a tensile strength of greater than or equal to 590 MPa, a hot-dip galvanized dual-phase steel, and a manufacturing method therefor by means of rapid heat treatment. The steel comprises the following components, in percentage by mass: 0.04-0.12% of C, 0.1-0.5% of Si, 1.0-2.0% of Mn, P?0.02%, S?0.015%, 0.02-0.06% of Al, and can further comprise one or two of Cr, Mo, Ti, Nb and V, wherein Cr+Mo+Ti+Nb+V?0.5%, and the balance is Fe and other unavoidable impurities. The manufacturing method therefor includes smelting, casting, hot rolling, cold rolling, and rapid heat treatment processes.