Objective To optimize spray cooling of solidification model surface in the process of continuous casting so as to realize the optimal cooling surface temperature. Methods The analysis of the continuous slab casting process was conducted, the solidi-fication model of continuous slab casting was deduced and the heat transfer equations were given to constraint boundary conditions of cooling process. The model of solidification simulation was verified and compared with the reference temperature change curve. In combination with a practical example, the target object needed to be optimized was determined during the cooling process. The genetic algorithm was adopted to search the optimal solution, and the relevant parameters were simulated. Results Compared with before simulation, the temperature fluctuation per unit time was small during the solidification process of slab after optimization and the maximum water flow density was about 35 L/ (m2·s). Conclusion The fluctuation of spray cooling temperature was evenly in the optimized process of continuous slab casting in unit time and the water quantity was less, avoiding cracks on the surface of slab caster solidification model and improving the quality of the products, which achieved better effects.