A　comprehensive　study　on　the　microstructural　evolution　of　a　new　type　Al-Zn-Mg-Cu-Er-Zr　alloy　during　homogenization　was　conducted　by　optical　microscope,　scanning　electron　microscope,　transmission　electron　microscopy　and　X-ray　diffraction　analysis.　The　results　show　that　serious　segregation　exists　in　as-cast　alloy,　and　the　primary　phases　are　T(AlZnMgCu),　S(Al2CuMg)　and　Al8Cu4Er,　which　preferentially　locate　in　the　grain　boundary　regions.　The　soluble　T(AlZnMgCu)　and　S(Al2CuMg)　phases　dissolve　into　the　matrix　gradually　during　single-stage　homogenized　at　465　degrees　C　with　prolonging　holding　time,　but　the　residual　Al8Cu4Er　phase　cannot　dissolve　completely.　Compared　with　the　single-stage　homogenization,　both　a　finer　particle　size　and　a　higher　volume　fraction　of　L1(2)-structured　Al-3(Er,　Zr)　dispersoids　can　be　obtained　in　the　two-stage　homogenization　process.　A　suitable　homogenization　scheme　for　the　present　alloy　is　(400　degrees　C,　10　h)+(465　degrees　C,　24　h),　which　is　consistent　with　the　results　of　homogenization　kinetic　analysis.