The utility model relates to the field of tension tests, and discloses an automatic weight loading device which comprises a plurality of weights (1) which are arranged in a stacked manner, and a controller (2), the lifting rod (2) is used for lifting one or more weights in the plurality of weights (1), and the top end of the lifting rod (2) is connected with power equipment; the ejector rod (3) isused for ejecting the lifting rod (2) to a preset position; the ejector rod (3) is provided with an ejector pin; the first driver (4) is used for driving the ejector rod (3) to ascend and descend; and the controller is used for controlling the first driver (4) to drive the ejector rod (3) to rise, and jacking the lifting rod (2) to a preset position so as to lift one or more weights in the plurality of weights (1).