A plant (10) for the continuous packing of food products in modified atmosphere (11), comprises a machine (12) for continuous packing of food products in modified atmosphere and conveyor (13) for the continuous sequential feeding of food products to the machine. A device (21) is present at the entrance of the machine (12) that temporarily submits a product fed by the conveyor (13) to vacuum and to a modified atmosphere before being packed in modified atmosphere in the machine.