Slat noise is largely dependent on its structure parameters which are geometry and morphing parameters. The investigation of the effects of these two parameters on the features of flow and noise for an airfoil is an effective method of developing techniques for the slat noise suppression. Firstly, Three-element airfoil model 30P-30N is employed to establish the model of investigation for analyzing the flow and noise features. Based on RANS and LES methods, steady and unsteady characteristics of the airfoil flow are studied for typical geometric (overlap, gap and rotation angle)and morphed profiles (morphed tailing edge of slat seals the gap). Then the corresponding distributions of pressure and turbulent kinetic energy are obtained. Secondly, FW-H acoustic analogy formulation is employed to solve the far-field noise radiation for the slat. The inter-relationship of various slat structure parameters with the far-field acoustic pressure level and its directivity features are investigated. Finally, based on various slat structure parameters and their flow and noise characteristics obtained, the interaction of slat noise attenuation and its corresponding lift changes are analyzed and discussed. The results show that the slat geometry and structural deformation parameters can effectively reduce far-field noise radiation, but the lift coefficient will be reduced to some extent when the angle of attack increases.