Abstract: A mobile harvester for loading and unloading hay bales made of a loading and unloading platform. The loading platform is positioned adjacent to and sidewise relative to a receiving platform which is adapted to individually and successively supply single rows of bales transversely on the loading platform. A first conveyor mechanism is mounted on the loading platform for longitudinally moving the bale with transversal channels for allowing the bales to transversally slide thereof and to longitudinally move the bales upon actuation of the first mechanism. The unloading platform is adjacently positioned lengthwise relative to said loading platform for receiving the bales from the loading platform when said first convyeor mechanism is moving. The unloading platform has a supporting surface which comprises a second conveyor mechanism for consecutively moving the bales longitudinally from one end substantially at the same level as the first mechanism to an end of the unloading platform opposite the loading platform.