【Abstract】 Objective To compare the clinical effect of proximal femoral nail antirotation (PFNA) internal fixation and joint replacement in the treatment of unstable intertrochanteric fractures in the elderly. Methods The clinical data of 84 elderly patients (> 75 years old) with unstable intertrochanteric fractures treated in our hospital from March 2012 to June 2015 were collected. According to different treatment methods, they were divided into PFNA group (n=44) and joint replacement group (n=40). The treatment effects, surgery related indicators, postoperative complications, hip function score and postoperative quality of life were compared between the two groups. Results The duration of surgery and blood loss of PFNA group were shorter and less than those of the joint replacement group (P<005). The time in bed, length of hospital stay and full weightbearing time of affected limbs of the joint replacement group were shorter than those of PFNA group (P<005), while the incidence of complications showed no significant difference (P>005). 1 year after surgery, the excellent and good rate of hip joint functional recovery in the joint replacement group was slightly higher than that in PFNA group (P>005). 1 year after surgery, the scores of daily living ability were significantly increased (P<005), and the increase in joint replacement group was more obvious than that in PFNA group (P<005). Conclusion PFNA internal fixation has little effect on internal environment of patients with unstable intertrochanteric fractures. The duration of surgery is short and blood loss is little. It is in accordance with the human biological characteristics and minimally invasive. The duration of hip replacement is long; and it has great effect on the internal environment, with large amount of blood loss but the hip joint function can recover quickly.