Objece Acetabular component failure has been proved to be the key factor affecting the long-term result of survival rate of TKR. Preparation of the acetabular for the component is the most important procedure for predicating the destiny of acetabular component. This study aimed to evaluate the side-effect of extensive concentric reaming for acetabular preparation in respect of bone loss of acetabulum rim and change of acetabular anteversion. Methods CT images of 40 normal adult bony acetabula were obtained and processed with the algorithm of histogram-threshold segmenting and Kirsh boundary detection to get a binary contour image. The contour of scanned acetabulum was then used for three-dimensional reconstruction with CAD software. With best-fit sphere of acetabulum bone joint surface technique, quantitative analyses have been done in computer imitating the concentric reaming for acetabulum. Two kinds of extensive concentric reaming for acetabular preparation were defined as reaming to the depth of reaching bottom of Harris forum or reaming until reaching the inner pelvic wall at medial side of acetabulum. Results (1) when it was done to the depth of reaching bottom of Harris forum, bone losses at anterior rim and posterior rim of acetabulum were estimated to average 6.75 mm and 6.11 mm respectively, and the acetabular anteversion was increased at upper half of acetabulum with maximum increase of 4.83°. (2) when it was done to the depth of reaching reaching the inner pelvic wall , bone losses at the anterior rim and posterior rim could reach to 9.54 mm and 9.56 mm thickness and acetabular anteversion at upper half of acetabulum further increased with maximum increase of 8.55°. Conclusion Although concentric reaming for acetabular would precisely maintain the normal hip kinematic center, extensive concentric reaming to the extent reaching or passing over the bottom of Harris forum could result in obvious bone losses at both anterior and posterior rims of acetabular bearing surface and alter the nature acetabular anteversion, which might compromise both the integration of acetabular component with bone surface and proper orientation of the component.