the hydrodynamic moment performance is vital to amphibian, in order to study the hydrodynamic moment performance of a amphibian, a moment performance tank test is conducted, the test model is a single hull model, the influence of trim angle, sea gauge of step and test velocity on the hull moment performance is systematically analyzed, and the test reliability is also demonstrated. The results turn out to be that this kind moment performance model test measure is of high reliability, the hydrodynamic moment increases with sea gauge and test velocity, and increases firstly then decreases with trim angle.