The prevention of hot-tearing in the commercial Al-Li alloys ingots (150mm×350mm) produced by DC casting was studied. Crack started at the caved part of ingot surface which was contaminated by oxide. The molten metal surface was ventilated by Ar gas to inhibit the generation and contamination of oxide. The stress by solidification shrinkage was reduced by decreasing casting speed, because the faster casting speed caused larger shrinkage. But the pouring temperature and coolant flow rate had no influence. No crack was detected in 2024 alloy. Shrinkage of Al-Li alloys was larger than 2024 alloy, and that was the one of the reasons why Al-Li alloy easily cracked. The faster casting speed causes the deeper sump.