The invention relates to an enclosure structure combined with prefabricated members and a mixing wall and a construction method. The enclosure structure is suitable for enclosure soil blocking and water stopping of foundation pits and riverways. The prefabricated members have two modes, namely, the city land assembling type H-shaped enclosure pile members and the water-stopping prefabricated centrifugal rectangular pile enclosure structures. The mixing wall is a continuous square cement-soil mixing wall and can be constructed through two construction methods, namely the TRD construction methodand the CSM construction method. The prefabricated members are pressed into the mixing wall according to the requirement to form enclosure. Compared with the prior art, the enclosure structure has the advantages that the bending and shear resistance is good, the brittleness is small, the ductility is good, the cost is low, the efficiency is high, pollution is avoided, multiple sections can be connected, and the enclosure structure can be constructed to be longer and deeper.