In noise level control, the surface acoustic property of noise sources is one of important initial information. The noise control will be more efficient and effective if we know not only the properties of noise source surface, but also know the most influential surface area to a certain target field location. If the dominant surface area of noise sources has been known, further treatment can be applied to the dominant surface area only. In order to be able to apply an appropriate further treatment, we must know how much acoustic quantity on the dominant area must be changed. Solving this problem needs inverse technique and optimization to obtain an optimal noise source characteristic. This paper presents a reconstruction method of multiple acoustic sources that fulfill the predetermined condition on a certain target field location using Boundary Element Method and Conjugate Gradient method. Test cases for radiation of multiple vibrating spherical shape sources in a certain area have been done for verifying the algorithm. Simulation results show that the proposed method could be used to reconstruct an optimal surface pressure of multiple acoustic sources