The invention discloses a making method of sweet potato balls, which achieves the advantage of simple and convenient operation through automatic operation, not only enables starch on the surfaces of the sweet potato balls to be uniformly coated, but also separates redundant starch, and is helpful for improving the making quality of the sweet potato balls. The potato ball making device is mainly composed of the main body mechanism, the supporting mechanism, the driving mechanism, the connecting assembly and the material guiding mechanism, through cooperative use of the main body mechanism, the supporting mechanism and the driving mechanism, the effect of automatic operation can be achieved, manual screening is not needed, the labor intensity of workers is reduced, and the production efficiency is improved. The screened potato balls and cassava starch can be collected through a first guide plate and a discharging pipe, and wide popularization and popularization are facilitated; and through the arrangement of the connecting assembly, the screening plate can be rapidly disassembled and assembled, independent cleaning of the screening plate is facilitated, the cleaning efficiency is effectively improved, and the making efficiency of the potato balls is further improved.