The invention relates to the field of civil engineering test equipment, in particular to a lever loading system and an assembling method. The ground anchor beam of the lever loading system provided by the present invention is connected with the floor anchorage, the main beam is arranged at a position parallel to the ground anchor beam and higher than the ground anchor beam; Lever, a plurality of levers are parallel to each other, and each lever is perpendicular to the main beam; one end of the lever is flexibly connected to the ground anchor beam through a steel wire, the other end is hung with a hanging basket, and the hanging basket is equipped with weights; the invention also provides The assembly method of the lever loading system is described. The lever loading system and assembling method have the advantages of simple loading, occupying less structural loading space, and adapting to the simulation of large uniform loads, etc., safe, reliable, and high stability, and can realize multi-point arrangement loading for the main beam, and realize fine and graded loading. , more accurately simulate the force pattern of the main beam, and it is convenient to observe the displacement of the main beam and the cracks on the side during the test process.