A study of scattering characteristics of S0 and A0 Lamb modes in an infinite isotropic plate with multiple damage is presented in this paper. Both plate theory and the wave function expansion method are utilized to derive the scattered wave field of a single damage. By using the addition theorems of Bessel functions, a complex scattering wave field of multiple damage is investigated. Measurements agreed well between theoretical results and FE simulations. Numerical results of a plate with two damage are graphically presented by considering S0 and A0 modes as an incoming Lamb wave. Effects of geometric properties of damage on the scattering wave field are discussed.