The invention provides a moving arm tower crane climbing beam supporting system and a using method thereof and relates to the technical field of building construction. The system aims at the problemsthat when an ultrathin shear wall is reinforced in the prior art, economy is poor, the high-altitude construction difficulty is large, and the safety risks are high. The system comprises at least three supporting frameworks arranged in parallel and at intervals, and multiple adjustable pull rod assemblies connected between the two adjacent supporting frameworks. Each supporting framework is connected with an embedded part bolt. A self-climbing device of a moving arm tower crane is fixed to the bottom supporting framework. A tower body is connected with the top supporting framework. The multiple adjustable pull rod assemblies are uniformly distributed on the outer side of the tower body. When the moving arm tower crane climbs, the third supporting framework is connected with the tower body,the second supporting framework and the third supporting framework are connected through the adjustable pull rod assemblies, constraint between the tower crane and the first supporting framework is loosened, the moving arm tower crane climbs upwards to the position of the second supporting framework and is connected with the second supporting framework, and so forth, it is always kept that vertical loads are borne together by the two adjacent supporting frameworks and the adjustable pull rod assemblies connected between the adjacent supporting frameworks.