Abstract: This study proposes a model to increase the heating efficiency of tundish plasma heating and improve the flow of molten steel in a tundish during production. A physical model was simulated based on the tundish prototype of a steel plant, and the temperature field and flow field of molten steel in the tundish with and without plasma heating at different plasma heating positions were analyzed. The research results showed that in the tundish without plasma heating, the proportion of the dead zone was high, reaching 36%. Moreover, the dead zone was mainly concentrated in the upper area outside the weir in the tundish. When the heating position was located outside the weir, it was found that there was little difference in the proportion of the dead zone between the tundish with and without plasma heating. The temperature near the heating position increased sharply, and the temperature difference of molten metal between the inside and outside of the weir was large. Moreover, the overall temperature distribution in the tundish was not uniform. When the heating position was located inside the weir, the proportion of the dead zone significantly decreased, reaching 29.2%. Further, the average residence time increased by about 57 s. The temperature of the outlet of the tundish increased significantly (about 7 ℃), and the temperature distribution in the tundish was uniform.