Abstract: The purpose of this paper is to investigate acoustic scattering by a prolate spheroid particle. As a verification of the feasibility, the BEM（Boundary Element Method）is first introduced for calculating acoustic scattering by a rigid spherical particle, which yields consist results with the theoretical values. Then the acoustic pressure distributions of the rigid prolate spheroid particle are presented when the aspect ratio and non-dimensional parameter change. However, due to the limitation of BEM, another method is introduced for calculating acoustic scattering of weak and gas fluid, which is characterized by approximating the acoustic scattering function. To validate the accuracy, the calculated reduced target strength of weak fluid is compared with the results shown in a previous paper. Then the acoustic scattering pressure distributions of bubbles (i.e. gaseous particles)are illustrated, corresponding to varied incident angles, aspect ratiosand non-dimensional parameters. The variation trends of the scattering cross section are discussed too. In the case ofbubbles, it is found that when the incident angle and non-dimensional parameter remain unchanged, the forward scattering grows as the axial ratio increases. When the non-dimensional parameter is far below 1, the scattering pressure distributes uniformly at each angle. For rigid particles and bubbles, it is shown that the forward scattering would gradually dominate when the non-dimensional parameter exceeds 4, the scattering side lobeswill be enhanced when the axial ratio increases, while the scattering cross-section will decrease.