The invention discloses a 3D printing reinforcement masonry shear wall structure and a construction method thereof. The construction method includes the following steps that a, the 3D printing technology is used for manufacturing a first layer of masonry outer shell to the pre-buried elevation position of transverse reinforcement; b, the transverse reinforcement is arranged on the top of the first layer of masonry outer shell; c, the 3D printing technology is used for manufacturing a second layer of masonry outer shell on the top of the first layer of masonry outer shell, and thus the transverse reinforcement can be laid in the masonry outer shell; d, the step b and the step c are executed repeatedly, so that the masonry outer shell is obtained; e, the step a and the step d are executed repeatedly, so that a plurality of masonry outer shells are obtained, and the masonry outer shells are stacked to the designed elevation of a shear wall; f, vertical reinforcement is mounted in each masonry outer shell; g, concrete is poured, and accordingly the shear wall can be constructed. By the adoption of the 3D printing technology, the masonry outer shells of reinforcement masonry can be integrally formed, original concrete small hollow blocks are replaced, the site construction labor force is greatly reduced, the construction procedures are omitted, the building quality is guaranteed, and thus building industrialization can be facilitated.