A systematic homogenization treatment on Al-Li-Cu-Mg-Mn-Zr alloy, within the temperature range from 500C to 540C for 24h or 36h was conducted. Microstructure and alloying elements distribution before and after homogenization treatment were studied by optical microscope, SEM, EDS and XRD. The results showed that in the as-cast condition Cu segregated at grain boundary and formed θ(Al2Cu) phase. With the homogenization temperature increased and time prolonged, the amount of the remained particles at grain boundaries decreased, and the alloying elements distribution became more homogeneous. It has been found that the homogenization temperature has more obvious effects on the microstructure and mechanical properties than time. However, the alloy homogenized at temperatures above 540C was overheated. Furnace cooling generates large amounts of precipitates in the matrix. The best homogenization parameter of the Al-Li-Cu-Mg-Mn-Zr alloy was determined as 530C for 24 h followed by air cooling.