A sheet feeding apparatus and an image forming apparatus are provided which can reduce the variability of overlapped portions when feeding sheets in an overlapping manner.When sheets are adsorbed to an adsorption conveyance belt, a suction shutter is switched from a block position to block a negative pressure to an adsorption position to adsorb the sheets by the negative pressure. When the sheets conveyed in an overlapping manner reaches a predetermined number and the next sheet is adsorbed, the timing to switch the suction shutter to the adsorption position is delayed compared to the timing at which a preceding sheet adsorbed in advance and a subsequent sheet overlap.