Disclosed is a hanging basket construction device for an asymmetric arc-shaped variable cross-section thin wing plate box girder. A hanging basket is composed of girder surface triangular main trusses, a bearing platform, a cable-stretching system, a traveling system, an in-position anti-push system, an anchoring system, an operation platform, a pre-buried part system and the like. The bearing platform of the hanging basket is formed by a combined structure of a box girder main frame and trusses, so that the rigidity of the hanging basket is effectively controlled, self-weight of the hanging basket is reduced, and the cost is reduced. An empty basket traveling task of the hanging basket is finished by means of traveling trolleys, traveling tracks, crab claw type sliding blocks, steel lifting belts, the girder surface inner-side triangular main trusses and a hauling mechanism. During usage, the crab claw type sliding blocks are reversely hooked on the girder surface inner-side triangular main trusses, the crab claw type sliding blocks are connected with a bearing platform girder by being connected with the steel lifting belts, the tail of the bearing platform is anchored to a girder bottom plate through traveling wheels, the hauling mechanism hauls sliding shoes to move forwards, therefore, the bearing platform is driven to move forwards, and the traveling mode is steady and reliable.