Objective To investigate the main factors in cannulated srew fixation of femoral neck fractures by the mechanical analysis of the curative effect of the closed reduction and internal fixation of the femoral neck fractures. Methods By August 2010 to October 2016, 47 patients with femoral neck fracture by closed reduction with cannulated screw fixation in our orthopaedic were studied, through single and multiple factor analysis, and the factors concluded the sex, age, operation time, preoperative traction, reduction quality, postoperative full weight-bearing time, Garden Type, removal of internal fixation. Results Logistic regression model of femoral head necrosis risk factors include: age, reduction quality (P < 0. 05) , and the rest are not significant. Conclusions The patient's age, reduction quality were the main factors affecting the femoral neck fracture healing, the mechanical fixation effect of cannulated screw is a good foundation for fracture healing.Therefore, the doctor may select the proper reduction mode according to the patient 's condition for a better therapeutic effect.