〔Abstract〕 Objective To assess the influence of inter-implant distances on the accuracy of intraoral scanning impressionsin vitro. Methods A master cast model with different inter-implant distances was scanned by laboratory and intraoral scanners, which were used as the reference and intraoral scan data. The distance and angular deviations of the scan bodies corresponding to the reference and intraoral digital scan standard tessellation language(STL) files were measured and calculated in a three-dimensional analysis software. The one-samplet-test, Spearman′s correlation analysis,Brown-Forsythe Ftest,Games-Howell post-hoctest, and Levene′s test were used for comparisons(α=0.05). Results The overall distance and angular deviations of the intraoral digital scan were(27.48±18.14) μm and(0.24±0.19) °, within clinically acceptable limits(P<0.001). The inter-implant distances exhibited a significant positive correlation with both the scanning distance and angular deviations in terms of scanning trueness. The angular deviation differed significantly between the 1-2 group(8.13 mm) and the other distance groups. Additionally, inter-implant distances affected the precision of the intraoral scanner(P<0.05). Conclusion The findings of this study indicate that intraoral scanning impressions of complete-arch implant-supported prostheses are within clinically acceptable ranges of accuracy. Inter-implant distances ≤ 8.13 mm can result in a higher accuracy of intraoral scanning. Increased inter-implant distances can adversely affect intraoral scanning accuracy.