Abstract: The effect of the angle of submerged entry nozzles, casting speed, and cross-section width of slabs on the surface fluctuation in a mold of Anyang Iron & Steel was researched with the VOF model of commercial software ANSYS CFX10.0. The results show that with the mold width increasing from 1 800 mm to 3 250 mm, the average wave height of liquid level in the mold decreases significantly. When the width is 1 800 mm, the average wave height of the mold flux-molten steel interface is 5.33 mm; when the width is 3 250 mm. the average wave height is 7.08 mm.