Effects of various minor Ce additions on microstructure and heat resistance of as cast Al 5.3Cu 0.8Mg 0.6Ag alloy have been investigated by tensile testing and TEM （transmission electron microscopy）.The results showed that the tensile strength at room temperature and heat resistance at high temperature of the as cast alloy can be improved by adding 0.20%～0.45% Ce at room temperature to 300 ℃.It is found that the Ce could refine the grain size of the alloy obviously and reduce Cu segregation in grain boundary.TEM indicated that minor Ce can refine strengthening Ω phase with increase in its precipitated density.A bulk Al x Ti 6Ce 3Cu compound appears in the as cast alloy which deteriorated sharply the tensile strength with adding both minor 0.2%Ce and 0.25%Ti.