Objective：To explore the risk factors of blade excessive lateral migration among femoral intertrochanteric fracture fixed with proximal femoral nail anti-rotation（PFNA）. Methods：A total of 163 intertrochanteric fracture patients（mean 69.9 years old）who received PFNA fixation from April 2011 to March 2016 in the Affiliated Hospital of Jiangsu University were retrospectively evaluated. There were 84 male patients and 79 female patients aged from 50 to 99 years（mean age of 69.6 years）. The radiological parameters were measured，including the condition of proximal lateral wall（broken or not），the position of lesser trochanter（displaced or not），tip-apex distance（TAD），calcar referenced tip-apex distance（Cal-TAD），the amount of lateral migration of the blade and medial cortex support mode. Singh index and AO/OTA type were also recorded. Logistic regression model was established to analyze the key factors causing excessive lateral sliding of blade. Results：We found that 18 cases showed radiographic over lateral migration. The univariate analysis illustrated that the excessive lateral migration of blade directly related to unstable fracture type，displaced lesser trochanter，and negative medial cortex support（P < 0.05），but not Singh index，calcar reduction，lateral wall injury，TAD，CalTAD，age and gender（P＞0.05）. Multiple logistic regression suggested that unstable fracture pattern and negative medial cortex support were independent risk factors of blade excessive lateral migration（P < 0.05）. Conclusion：For femoral intertrochanteric fracture patients treated with PFNA，over lateral sliding of blade may occur. The risk factors include unstable fracture pattern and negative medial cortex support. PFNA should be used cautiously in those with the hazard factors，and weightbearing ambulation must be delayed.