The invention discloses an assembly-type steel structure out-hanging wall plate joint convenient to install and mold. The assembly-type steel structure out-hanging wall plate joint convenient to install and mold comprises an outer wall plate and an out-hanging wall plate, wherein the outer wall plate is divided into an upper layer outer wall plate and a lower layer outer wall plate, and a supporting plate is arranged between the upper layer outer wall plate and the lower layer outer wall plate; a prefabricated embedded part is arranged at one end of the out-hanging wall plate, and the out-hanging wall plate is connected with the upper layer outer wall plate through a first angle steel assembly; the lower portion of the out-hanging wall plate is provided with a support frame, the support frame is connected with the lower layer outer wall plate through a connecting plate, and the lower portion of the connecting plate is fixedly connected with the lower layer outer wall plate through a second angle steel assembly. The assembly-type steel structure out-hanging wall plate joint convenient to install and mold and the construction technology thereof are further improved and installed in the construction process based on the existing vertical-assembly wall plate swing construction method, and a wall plate and the outer wall plate are fixedly connected, so that the stability of connection between the wall plate and the outer wall plate and the using safety are further improved.