The invention discloses an assembling and welding device which comprises a rotating disc device, a first automatic feeding device, a second automatic feeding device, an automatic discharging device and a welding device. The rotating disc device is positioned in the middles of the first automatic feeding device, the second automatic feeding device and the automatic discharging device, so that assembly elements are conveniently and rapidly fed and discharged. The assembling and welding device has the advantages that when the assembling and welding device is used for production, elements to be integrally assembled are respectively placed on a first jig and a second jig by only one operator, the rotating disc device, the first automatic feeding device, the second automatic feeding device, the welding device and the automatic discharging device are mutually matched to perform assembling and welding after the assembling and welding device is started, finally, finished products are taken out from a third jig, the assembling and welding device is simple to operate and high in production efficiency, furthest automated operation can be realized, and labor is greatly saved.