Based on EulerianLagrangian coupling algorithm, the performance parameters of Fanshaped airblast atomizer is simulated. It is shown that when gasliquid mass flow ratio is constant, the spray angle and velocity of droplet decreases and SMD increases gradually with the increase of orifice width. Therefore, in order to obtain much smaller liquid droplet, orifice width should not be too wide. When the orifice width is constant, along with the increase of gasliquid mass flow ratio, SMD decreases firstly and increases later when reaching the minimum. And SMD minimum value is 39.5 μm when the orifice width is 0.6 mm.