The utility model discloses a kind of semi-trailer unloading devices, belong to semi-trailer field, including semi-trailer, the top of semi-trailer is fixedly connected with vertical plate, the top of semi-trailer is rotatably connected with several conveying rollers;The top of semi-trailer is fixedly connected with two protective plates, the top inside of protective plate is fixedly connected with three electric push rods, the bottom output rod of electric push rod is fixedly connected with driving frame, the inside sliding connection of driving frame has two round rods;Through the cooperation of above each device, by setting object carrier plate, it is placed to predetermined position, by the cooperation of insert block and clamping groove to limit object carrier plate, not only improve the stability of object carrier plate in the process of transportation, also provide guarantee for the stable transportation of goods, the two protective plates of the top of semi-trailer can also play certain limiting effect to goods, reduce the collapse accident caused by goods due to inclination, greatly reduce the wobble of object carrier plate in the process of transportation.
