Abstract: The mechanical properties of ship plate steel, such as yield strength, tensile strength, reduction of area and impact energy, are decided by the microstructure and steel composition. Therefore, it is highly advised to minimize the effect of chemical composition fluctuation on the mechanical properties. This paper established a mathematical model of sulfur content and mechanical properties of DH36 ship plate steel under different element content by applying the industrial production data and Matlab software. The results show that impact energy of the DH36 ship plate steel increases first, then drops, with the rising sulfur content. The yield strength, tensile strength and section reduction rate of DH36 ship plate steel are observed in a nonlinear relationship with the sulfur content, the tendency relating to the contents of other elements.