The utility model discloses an assembled mixed structure system suitable for high residential building building is applicable to stairwell, escalator and offsets in the building structure of architectural plane one side, including steel -frame pillar, girder steel, bearing structure and an assembled core section of thick bamboo, steel -frame pillar comprises steel pipe -concrete composite dysmorphism post and steel core concrete column, steel pipe -concrete composite dysmorphism post comprises at least three limb posts, the special -shaped post insertible building wall of steel pipe -concretecomposite and not exposing, bearing structure comprises steel shotcrete component or shear force wall, an assembled core section of thick bamboo is arranged in stairwell and escalator, bearing structure sets up in party wall and headwall, the girder steel with steel pipe concrete special -shaped column rigid connection, the girder steel with an assembled core section of thick bamboo is articulatedto be connected. The utility model discloses lateral load resistance component arranges that easily head beam dew post, on -the -spot wet trade work load are greatly, building escalator noise is bigand steel column base is difficult to handle the scheduling problem in inconvenience, the room in can solving the residential housing.