Abstract: A bag opening machine has an endless conveying band provided with spikes which conveys a bag (impaled on the spikes thereof--when in an extended position) to and past cutting means which act to make a continuous cut around three sides of the bag so that after cutting thereof it comprises two halves joined only at the rear or trailing side of the bag, unfolds the two halves of the bag as the half thereof engaged by said spike members is drawn to the forward end of the conveyor, thus to empty the contents of the bag into receiving means therefor and releases the emptied bag (by retraction of said spike members) to collection means therefor.