According to one embodiment, a sheet ejection apparatus includes an ejection unit (124), a thickness detection unit (129), a thickness storage unit (121b), a sheet detection unit (128), an acquisition unit (121a), a setting unit (121a), and an adjustment unit (121a). The ejection unit ejects a sheet. The thickness detection unit measures a thickness of the sheet. The thickness storage unit stores thickness information. The acquisition unit acquires a thickness of a preceding sheet. The setting unit sets a gap between the preceding sheet and the sheet in accordance with the thickness of the preceding sheet. The adjustment unit adjusts timing for supplying the sheet to a conveyance path in accordance with the gap.