In this study, the roll casting of Al-40%Sn-1%Cu alloy was tried by an unequal diameter twin roll caster. The unequal diameter twin roll caster could continuously cast the strip. The casting load of the roll was small to prevent the flow out of the Sn. The roll-load was 0.1kN/mm(unit width). The roll casting of 400mm-width strip of 8mm-thick was tried, and it was attained. The gravity segregation of Sn did not occur. The as-cast strip could be cold rolled down to 1mm. However, this strip had much porosity. The rapid solidification was useful to prevent the porosity. The copper roll was better than steel roll to increase cooling ability. The copper roll was suitable to prevent the porosity. The temperature of solidified metal was important factor which influenced the porosity. The 4mm-thickness strip with little porosity was could be cast at the speed of 30m/min.