The　scanning　electron　microscopy　and　transmission　electron　microscopy　were　used　to　analyze　the　distributional,　compositional　and　microstructural　characteristics　of　the　complex　alloy　phases　(CAPs)　formed　in　the　as-cast　Al75Pd15Fe10　alloy.　For　the　two　CAPs　formed　during　the　solidification,　the　local　and　long-range　features　determined　by　the　arrangement　of　atom　clusters　were　compared,　and　also　the　formation　conditions　were　discussed.　The　results　show　that　there　exist　two　kinds　of　CAPs　formed　through　different　phase　transition　processes　but　containing　same　type　of　columnar　atom　clusters　with　1.6　nm　periodicity　as　the　basic　structural　building　blocks.　The　two　CAPs　belong　respectively　to　a　decagonal　quasicrystal　with　defects　of　high　density　and　defective　crystalline　phase　(Ε16).　Prior　to　the　formation　of　the　Ε16　crystalline　structure,　the　quasiperiodic　structure　forms　at　higher　temperature.　Within　the　compositional　range　suitable　for　the　formation　of　an　Al-Pd-Fe　complex　structure,　increasing　the　Pd-content　and　slowing　down　the　solidification　rate　will　be　favorable　to　form　atom　clusters　with　structural　integrity,　and　also　favorable　to　increase　the　distributional　density　and　establish　long-range　periodicity　for　the　arrangement　of　atom　clusters.