Background: To evaluate and compare the clinical outcomes of digitally prefabricated and conventionally fabricated implant-supported full-arch provisional prostheses.Methods: Thirty-nine patients who underwent implant-supported full-arch rehabilitation were included in this study. Implant-supported provisional prostheses were digitally prefabricated before implant surgery in group A (20 patients), while implant-supported provisional prostheses were conventionally fabricated immediately after surgery in group B (19 patients). Implant/prosthesis survival rate and complications were recorded. Marginal bone loss（MBL）was investigated by CBCT. Surgical time, restorative time, and total operative time were analyzed. Postoperative pain and swelling were evaluated with visual analog scale (VAS). The Oral Health Impact Profile (OHIP) questionnaire was administered before and after surgery.Results: The implant/prosthesis survival rate was 100% and complications appeared with low frequency in both group, while the mean MBL was 0.30±0.29 mm in group A and 0.31±0.41 mm in group B after 3~6 months(P>0.05). The average restorative time in group A (116.16±16.61 mins) was significantly shorter than that in group B (242.11±30.14 mins) (P<0.05). Patients in group A showed lower pain/swelling VAS scores after surgery than group B (P<0.05). Low OHIP scores with high satisfaction to the overall effects were showed in both groups. Conclusions: Prefabricated prosthesis could reduce prosthetic time and postoperative discomfort in patient whose immediate rehabilitation was based on All-on-4 concept. The prefabrication technology could be a predictable alternative to improve the short-term clinical outcome of implant-supported full-arch provisional rehabilitation.