Abstract: A high-strength multi-phase steel having minimum tensile strengths of 750 MPa and preferably having a dual-phase microstructure for a cold- or hot-rolled steel strip, in particular for lightweight vehicle construction is disclosed. The high-strength multi-phase steel has improved forming properties and a ratio of yield point to tensile strength of at most 73%. The high-strength multi-phase steel includes in mass %: C?0.075 to ?0.105; Si?0.600 to ?0.800; Mn?1.000 to ?0.700; Cr?0.100 to ?0.480; Al?0.010 to ?0.060; N 0.0020?0.0120; S?0.0030; Nb?0.005 to ?0.050; Ti?0.0050 to ?0.050; B?0.0005 to ?0.0040; Mo?0.200; Cu?0.040%; Ni?0.040% the remainder iron, including typical elements accompanying steel that are not mentioned above, which represent contamination resulting from smelting.