The invention discloses an automatic joint scraping machine. The automatic joint scraping machine comprises a supporting base, a rotating disc, a first automatic joint scraping mechanism, a second automatic joint scraping mechanism and a bottle washing mechanism, wherein the appearance of the rotating disc is circular. Multiple stations used for fixing the bottle blanks are arranged on the rotating disc. A feeding station, a primary bottle scraping station, a secondary bottle scraping station, a bottle washing station and a discharging station are arranged on the automatic joint scraping machine. The first automatic joint scraping mechanism, the second automatic joint scraping mechanism and the bottle washing mechanism are located at the primary bottle scraping station, the secondary bottle scraping station and the bottle washing station correspondingly. A mounting disc with the appearance being circular is arranged on the supporting base. The mounting disc is located below the rotating disc and is provided with a fixing mechanism used for fixing the bottle blanks, bottle rotating mechanisms and an automation mechanism. The fixing mechanism, the bottle rotating mechanisms and the automation mechanism are located at the primary bottle scraping station, the secondary bottle scraping station and the bottle washing station correspondingly. The automatic joint scraping machine has the advantage of being high in automation level; production efficiency is improved; manpower is saved; the labor intensity of workers is reduced; and the machining quality of products is guaranteed.