Objective To explore the impact of preoperative traction on the osteonecrosis of the femoral head (ONFH) in patients with femoral neck fractures. Methods Between February 2013 and May 2016, 120 patients with femoral neck fractures, who were treated with screw fixation, were collected. Sixty patients with fractures of Garden type Ⅰ and Ⅱ were non-displaced fracture group; 60 cases with fractures of Garden type Ⅲ and Ⅳ were displaced fracture group. The patients in 2 groups were randomly divided into traction and non-traction subgroups (n=30). There was no significant difference in gender, age, injury mechanism, damage side, the time from injury to operation, and fracture classification between 2 subgroups (P>0.05). Intracapsular pressure was recorded before operation. The quality of fracture reduction and the satisfaction ratio of screw implant were evaluated during operation. Visual analogue scale (VAS), Harris score, joint mobility, and the incidence of ONFH would be evaluated at 6 months, 1 year, and 2 years after operation. Results All incisions of 2 groups healed by first intention after operation. There was no infection or deep vein thrombosis of lower extremity. All patients were followed up 2 years. In displaced and non-displaced fracture groups, the intracapsular pressure of traction subgroups were higher than that of non-traction group (P<0.05); the differences of the quality of fracture reduction and the satisfaction ratio of screw implant were not significant (P>0.05) between 2 subgroups. At 6 months, 1 year, and 2 years after operation, VAS scores were higher in traction subgroup than in non-traction subgroup (P<0.05); and the joint mobility and Harris scores were lower in traction subgroup than in non-traction subgroup (P<0.05). X-ray films showed all fractures healed. Except for the non-displaced group at 6 months, the incidences of ONFH were higher in traction subgroup than in non-traction subgroup at other time points (P< 0.05). Conclusion Preoperative traction may increase the risk of ONFH, which can increase the intracapsular pressure and affect the blood supply of femoral head.