The flow and heat transfer of molten steel in the mold can be controlled by changing the outflow direction of the molten steel in the side hole of the nozzle, and the effects of different outlet directions of submerged entry nozzles on the fluid flow, heat transfer, and solidification behavior in the bloom continuous casting mold were analyzed by using hydrodynamics and solidification simulation methods. The results showed that the direction of side hole had a significant effect on the flow and solidification behavior of molten steel in the mold during casting. when the horizontal rotation angle of the nozzle side hole was 30°, a favorable horizontal swirling flow can be produced in the mold, which can effectively reduce the jet impingement of molten steel flowing from the side hole on the solidifying shell, together with an increasing meniscus temperature. Comparing the different outlet angles of side holes, it was also found that the swirling flow effect of ordinary radial quadruple nozzle produced under certain installation angle not only has a beneficial effect on the uniform growth of primary shell and the metallurgical effect of the mold, but also can obtain the swirling flow effect similar to that of MEMS even without changing the nozzle structure.