Liquid sloshing will affect dynamics and control of aircraft. In order to reduce the negative impact of liquid sloshing， this paper proposes several sloshing suppression design schemes for common Cassini tanks from the perspective of passive control， and explores influences of different factors on the sloshing suppression performance. After comparing and analyzing the performance of annular baffle tank， fan baffle tank and annular floating plate tank by FLOW3D， a compound structure tank with baffle plate is proposed， and the feasibility is verified by a comparative study.