[Objective] To investigate the early clinical results of total hip arthroplasty (THA) assisted with three-dimensional preoperative planning. [Methods] Eight THAs assisted with three-dimensional preoperative planning from May 2019 to June 2018 were retrospectively analyzed. CT scan was redone after surgery to examine the results of surgery compared to the pre-operation planning. The Harris score and the Western Ontario McMaster (WOMAC) Osteoarthritis Index were recorded and compared before and after operation. [Results] The acetabular inclination angle was 41.6±4.6°postoperative, the acetabular anteversion angle was 19.1±5.6°postoperative, the femur anteversion angle was 14.4±6.3° postoperative, leg length was changed 0.4（-2.025~0）mm postoperative. Compared with 3D preoperative planning, in acetabular side, 6 cases were same, 1 case was different in one size, 1 case different in 2 sizes; in femur side, 3 cases were the same, 3 cases were different in one size, 2 case different in 2 sizes. The WOMAC score and Harris score were significantly improved (P<0.05). [Conclusion] Preoperative 3Dplanning is valuable for size choosing and proper positing of component implantation during THA.