Abstract: The chemical composition of 600 MPa grade hot-rolled dual phase steel coiled at medium temperature was designed according to the characteristics of a CSP short process production line,and the dynamic CCT curve of the steel was measured.The effect of finishing temperature on the microstructure and mechanical properties of hot rolled plates was studied.The results show that when the finishing temperature changes in 821-858℃, the microstructure of the hot rolled plate is composed of ferrite and martensite.With the increase of finishing rolling temperature, the volume fraction of ferrite increases slightly from 84.60%to 85.14%, while the grain size of ferrite increases obviously from 5.07 μm to 5.97 μm.Under different finishing temperatures, the tensile strength reaches more than 600 MPa, the elongation is above 24.0%, meanwhile the stress-strain curves all show continuous yield.But with the increase of the finishing temperature, the yield strength of the hot rolled plates tends to decrease, when the finishing temperature reaches 858℃, the yield strength of the hot rolled plate (322 MPa) is lower than the performance requirement (more than 325 MPa) of DP600 steel.The reasonable finishing temperature specification for DP600 steel should be (830±15) ℃according to the characteristics of CSP line and the performance requirement of DP600 steel.