Objective: To compare the clinical outcome of anterolateral minimally invasive approach versus conventional posterior approach for total hip replacement against femoral neck fractures in elderly patients.Methods: The retrospective study was carried out on 42 patients who suffered from displaced femoral neck fractures (19 cases of Garden type Ⅲ, 23 cases of Garden type Ⅳ) treated by total hip replacement via anterolateral minimally invasive approach or conventional posterior approach by the same experienced surgeon. The average age of the patients was 78.1 years (range: 65-89 years). They were divided into anterolateral mini-invasive group (22 cases) and posterior group (20 cases). The mean time of follow-up was 13 months (range: 6-36 months). The anterolateral approach described by Hardinge goes through between anterior 1/3 and posterior 2/3 of the gluteus medius muscle, reaching the femoral neck from anterior capsule. The traditional posterior approach described by Moore (Southern incision) goes through the insertions of short external rotation muscles,reaching the femoral neck from posterior capsule. The related variables under observation were length of incision,operation time, postoperative limp, length of hospital stay and bed stay and dislolcation rate.Results: The length of the skin incision varied between 7 cm and 12 cm with the anterolateral minimally invasive technique, compared to 15-22 cm in the conventional procedure. It took less time (average 15 minutes) to complete the anterolateral minimally invasive approach (72 min±15 min), compared with the conventional approach (87 min±10 min). The average Harris hip score was 91.23±10.20 inanterolateral approach, 90.03±11.05 in the posterior approach. The average length of hospital stay for patients with the anterolateral approach was (6.4±2.2) days (range:4-9 days), while that in posterior approach was (9.2 ±3.1)days (range: 6-13 days). The average length of bed stay was (3.4±1.1) days (range: 2-5 days) in anterolateral group and (6.2±2.8) days (range: 3-10 days) in posterior group. No patients in anterolateral group experienced dislocation. One (5%) hip in posterior approach had dislocation.Conclusions: Anterolateral mini-invasive approach can decrease trauma, operation time, length of hospital stay and bed stay and rehabilitation time. The stability and minimal muscular damage permit the acceleration of postoperative rehabilitation, which can subsequently reduce the perioperative risk in the treatment of femoral neck fractures in the elderly undergoing total hip replacement.