A sheet stacking apparatus includes a stacking portion, a conveyance portion configured to convey the sheet toward the stacking portion, an abutting portion against which a leading edge of the sheet in the sheet conveyance direction is abutted, a first conveyance member, a second conveyance member movable to a contact position at which the second conveyance member contacts the sheet stacked on the stacking portion and to a retracted position to which the second conveyance member is retracted from the sheet stacked on the stacking portion, and a control portion configured to execute a first mode in which the second conveyance member is positioned at the contact position and a second mode in which the second conveyance member is positioned at the retracted position.