The invention discloses a stable irregular steel structure building which comprises a main body structure, a roof truss structure and a curtain wall structure, wherein a floor steel beam structure and a floor truss structure are arranged in the main body structure; the roof truss structure is arranged above the main body structure; inner support columns, side support columns and transverse support columns are arranged inside the curtain wall structure; the inner support columns are arranged below the roof truss structure; the side support columns are arranged below the periphery of the roof truss structure; the transverse support columns are arranged in transverse directions of the side support columns. According to the stable irregular steel structure building, the floor steel beam structure and the floor truss structure are additionally arranged in the main body structure, a complete steel structure building is achieved indeed, meanwhile with the combination of the structures with the roof truss structure and the curtain wall structure, good stability and support properties of the whole building can be achieved, particularly due to the curtain wall structure, not only is simple support achieved, but also requirements of users on shapes are met, and furthermore construction requirements can be relatively well met.