The characteristics of entrainment by jet flow in the spray semi-dry flue gas desulphurization tower have an important influence on the mixing of the flue gas and the absorbent in the tower and the uniform distribution of the flow field. In this paper, the characteristics of entrainment by jet flow of the two-fluid atomizing nozzle are analyzed by numerical simulation method, and the jet flow field distribution in the spray semi-dry flue gas desulfurization tower is obtained. The results show that the jet flow field distribution of the two-fluid atomizing nozzle presents small on both sides of the middle and reflux occurs on both sides of the tower wall; the jet flow fluid exchanges momentum with the surrounding gas and have an obviously entrainment to the surrounding gas. The jet entrainment volume increases gradually along the jet axis direction and with the increase of the amount of wind, the entrainment volume of the jet also gradually increases.