The invention provides a metal powder-cored wire for high-speed welding of engineering machinery. The metal powder-cored wire comprises a steel tape sheath and a metal powder core wrapped in the steel tape sheath, wherein the metal powder core comprises the following components with the contents in percentage by mass: 11-13% of nickel powder, 3-4% of ferrosilicon, 1.0-2.0% of ferroaluminium, 12-14% of silicon-manganese alloy, 1.5-2.5% of silicon carbide, 4-6% of ferroboron, 0.3-0.75% of potassium titanate, 4.5-5.5% of ferromolybdenum and the balance iron powder and inevitable impurities. The metal powder-cored wire provided by the invention is welded by virtue of 75-80% of Ar and 20-25% of CO2 protective gas, and the comprehensive performance of the deposited metal and the welding joint of the metal powder-cored wire are as follows: the yield strength is not less than 550MPa; the tensile strength is 670-770MPa; the elongation is not less than 22%; KV2 is not less than 50J under the condition of minus 60 DEG C; and a stable electric arc and extremely less slag after welding are achieved.