Abstract: Objective: To compare the effects of the proximal femoral nail antirotation(PNFA) between lateral decubitus and supine position in the treatment of intertrochanteric femur fractures in the advanced age patients.Methods: Twenty advanced age patients with intertrochanteric femur fractures were treated with PFNA in lateral decubitus and supine position.The operating time,postoperative tip-apex distance(TAD) and Harris hip score were observed,and the curative effects between two positions were compared.Results: The average operation time in patients with the lateral decubitus position (42.6±7.4) mins was shorter than that in patients with supine position (97.5±38.82) mins(P<0.01).All patients were followed up for 8 to 21 months,and the following up time in 18 cases were more than 1 year.The Harris hip score and TAD in patients with the latral decubitus position and supine position were (84.9±3.45)point & (87.2±5.6)point and (20.2±4.89)mm & (21.5±4.86)mm,respectively,the difference of which was not statistically significant(P>0.05).Conclusions: Compare with the supine position,the PNFA in latral decubitus position in treating the advanced age patients can simplify the operative process,and the long-term effect of which is satisfactory.