The invention discloses application of a water reducer great in water reduction performance and resistant to mud in recycled aggregate concrete of architecture solid waste. The invention also providesthe recycled aggregate concrete of the architecture solid waste, wherein the recycled aggregate concrete contains the water reducer great in water reduction performance and resistant to mud. The water reducer great in water reduction performance and resistant to mud is based on a macromolecular structural design principle and formed by polymerizing activated monomers containing phosphorous acid functional groups and sulphonic acid functional groups, the macromolecular structure is in a ball shape and contains a great number of amidogen radicals containing positive charge, and therefore the water reducer has superior properties such as great water reduction performance, excellent slump loss resistance and high clay tolerability. The water reducer is used alone or cooperates with other functional polycarboxylate water reducers for use and has excellent water reduction performance and great slump loss resistance for the recycled aggregate concrete of the architecture solid waste.