This study has been carried out to examine into wettability of Cu-5%Sn alloy in AL₂O₃, MgO, SiO₂and graphite, respectively and investigated into the change in macrostructure of Cu-5%Sn alloy according to kind and mixing rate of mold-coating. The results obtained from the experiment are summerized as follows; 1. Cu Cu-5%Sn alloy, wettabilities of Al₂O₃and MgO were good, on the other hand, wettabilities of SiO₂and graphite were bad. 2. The fine equiaxed zone was created because of the role of Al₂O₃and MgO as preferential nucleation sites. 3. Notwithstanding change of mixing rate of SiO₂in mold coating the equixed zone was not created. 4. The area of equiaxed zone was varied according to mixing rate in the case of using Al₂O₃and MgO in mold-coating.