The retrospective study aimed to verify the application of preoperative digital registration combined Cone Beam Computed Tomography (CBCT) and Intraoral Scan (IOS) on implant placement by the semi-active robot. A total of forty-six implants in forty participants have been included in the retrospective study. The participants were divided into two groups: the double CBCT registration and the digital registration groups. The deviations between preoperative planned and intraoperative placed implants were compared and analyzed. Data were statistically analyzed by the SPSS. Mann-Whitney U test was performed for post hoc comparisons (α = 0.05). Stable and high accuracy of implant placement could be achieved by the semi-active robot using preoperative digital registration method, although statistical difference was observed in the lateral apical deviation between the two groups. The preoperative digital registration method may be an alternative to traditional preoperative double CBCT registration method.