Abstract: A continuous casting mould with a cross section of 1 400 mm × 230 mm was simulated by software Fluent 6.3, and the effects of casting speed, immersion depth and submerged nozzle (SEN) opening-angle on its flow field were investigated. It is shown that with the increase of casting speed, the maximum horizontal and vertical velocities of the liquid surface increase, and the position of the impact point on the narrow side does not change. With the increase of distance to the liquid surface, the velocity of the narrow side first increases and then decreases, till near to zero. When the casting speed is greater than 1.2 m·min^-1, the horizontal velocity of the liquid surface obviously increase. With the increase of SEN immersion depth, the maximum horizontal velocity of the liquid surface decreases, and the maximum vertical velocity increases. SEN immersion depth has little effect on the impact point on the narrow side. When the SEN immersion depth is greater than 140 mm, the change of the maximum horizontal velocity is small. With the increase of SEN downward opening-angle, the maximum horizontal velocity of the liquid surface first decreases and then increases. When the SEN downward opening-angle is 12.5°, the maximum horizontal velocity of the liquid surface is the smallest, but the minimum velocity at the impact point on the narrow side can be obtained when the SEN downward opening-angle is 10° to 12.5°. KEY WORDS