Abstract: The effect of heredity phenomenon on the structure properties of ZL201 alloys is investigated by floating casting.The mechanism of heredity is discussed by analysising the solidification characteristic.The result shows that the adding of floating agent makes solidification time shorten,speed fast,and alloy structure refined.The view-point for which the dispersed particles in molten metal are a gane of structure heredity is proved,the alloy structure can be improved obviously and the mechanical properties σ band δ may be increased by 8.8% and 23.1%.