Abstract: Objective To compare the curative effect of arthroscopic and open surgeries for retrograde intramedullary interlocking nails(RIIN) in the treatment of femoral supracondylar fracture. Methods A total of 40 patients with femoral supracondylar fracture underwent either arthroscopic (n=20) or open surgeries (n=20) for rRIIN. Results The operation time, surgical blood loss and bone union time in arthroscopic group was less than that in the open surgery group (P<0.05). Follow-up of the patients for 10.3±3.6 months revealed excellent results in 15 cases, good in 3 cases, and acceptable in 1 case in the arthroscopic group, according to the Kolmert criteria, while excellent in 7, good in 14, acceptable in 4 and poor in 2 cases in the open surgery group, without statistically significances in the rate of good or excellent outcomes between the two groups (90.0% vs 75.0%, P=0.246). Conclusion Compared with open surgery, RIIN shortens the operation time, reduces intraoperative blood loss and accelerates bone union, thus benefiting the recovery of knee joint functions.