The invention relates to a dry-hanging, sealing and jointing treatment construction method for building wall decoration stone. A first support base, a second support base, a support mechanism, a dustremoval mechanism and a jointing mechanism are included, wherein one side of the first support base is connected with the second support base, the support mechanism is arranged right above the first support base and the second support base, the jointing mechanism is mounted at the upper end of the support mechanism, the dust removal mechanism is mounted on the upper end surface of the jointing mechanism, first inserting connection barrels are installed at the top of the first support base, first positioning rods and tooth groove rods are sequentially mounted in the three first inserting connection barrels, bearings A are mounted in connection positions of the first positioning rods and the tooth groove rods with the first inserting connection barrels, a first motor is mounted at the cornerof the upper end surface of the first support base, a first driving wheel is welded at an output shaft of the first motor, and a first belt is mounted on the outer side of the first driving wheel ina matched manner. The operation is simple and safe, and the sealant injection process is uniform, compact and full.