Steel plate with high strength and low yield ratio

The present invention provides a steel plate with high strength and low yield ratio, which comprises chemical components as follows: C: 0.15-0.20 wt%, Si: 1.0-2.0 wt%, Mn: 1.8-2.0 wt%, Al<=0.036 wt%,V: 0.05-0.1 wt%, P<=0.01 wt%, S<=0.005 wt%, Cr: 0.8-1.0 wt%, the residual is Fe and other unavoidable impurity. The hot-rolling steel plate with high strength and low yield ratio is obtained by adopting low alloyed processing and traditional TMCP rolling technique, which has a strength reaching to 1200-1500 MPa, simultaneously, has better low temperature impact toughness. The steel plate is suitable for the fields requiring high strength and low yield ratio, such as mechanical manufacture, fuel/gas delivery pipeline, building, bridge, steel rail and pressure vessel, etc.