The invention discloses a forming device for additive manufacturing based on ceramic material. The device is characterized in that the device comprises a light-curing mechanism, a driving mechanism and an extrusion and pumping mechanism. The light-curing mechanism is arranged on one end of the extrusion and pumping mechanism. The driving mechanism is arranged at the other end of the extrusion and pumping mechanism. The light-curing mechanism comprises a light adjuster (15), an ultraviolet lamp fixing plate (16) and an ultraviolet curing lamp (17). The extrusion and pumping mechanism comprises a nozzle (1), a nozzle connecting part (2), a screw rod (3), a charging barrel (4) and a hopper (6). The driving mechanism comprises a motor (12) and a coupler (11). The invention further discloses a forming method for additive manufacturing applying the device. The method is capable of continuously and uniformly extruding ceramic light-cured slurries with 0 vol%-65 vol% in solid content of ceramics; light-curing operation is performed while deposition forming is carried out; the solid content of ceramics is high; and density of forming blank after sintering is high.