Abstract: Tin can be easily oxidized in its molten state, generating a lot of dross. It affects tin's usage heat tin plating and soldering. This paper studies the effects of Y on antioxidative properties by analyzing its microstructure, liquid surface color change of tin melt at high temperature, wettability and its mechanism. The optimal Y adding amount is determined. The results indicate that Y element improves significantly the oxidation resistance behavior and wettability of molten tin.