Objective To compare the efficacy between percutaneous compression plate (PCCP) and cannulated compression screw for undisplaced femoral neck fracture among the elderly.Methods A retrospective case-control study was made on 46 elderly patients with undisplaced femoral neck fracture between August 2011 and September 2015.There were 14 males and 32 females,with the age of (76.9 ± 12.1) years (range,60-85 years).The fracture types included Garden Ⅰ in 12 patients and Garden Ⅱ in 34.These patients were divided into PCCP group (PCCP for undisplaced femoral neck fracture in 23 patients) and cannulated screw group (three cannulated compression screws for undisplaced femoral neck fracture in 23 patients),according to different surgical fixations.The following data were compared between two groups,namely,operation time,intraoperative blood loss,postoperative hemoglobin decline,postoperative length of hospital stay,postoperative partial time of weight-bearing and full weight-bearing,fracture healing time,Harris hip score (HHS) as well as postoperative complications.Results All 46 patients were followed up,with follow-up duration for (34.6± 15.3)months (range,12-60 months) in PCCP group and for (32.9 ±17.3) months (range,12-60 months) in cannulated screw group (P ＞ 0.05).There were no statistically significant difference between two groups in terms of operation time,intraoperative blood loss,postoperative hemoglobin decline,postoperative length of hospital stay,fracture healing time,and postoperative full weight-bearing time (P ＞ 0.05).The partial weight-bearing time of patients in PCCP group was earlier than that in cannulated screw group (P ＜ 0.05).The HHS of patients at postoperative 3 months in PCCP group was better than that in cannulated screw group (P ＜ 0.05),but the HHS at the final follow-up had no statistically significant difference between two groups (P ＞ 0.05).There was no statistically significant difference in the incidence of postoperative complications between PCCP group (9％) and the cannulated screw group (13％) (P ＞ 0.05).Conclusions Usage of PCCP or cannulated compression screw can obtain satisfactory clinical results for the undisplaced femoral neck fracture among the elderly.But PCCP has the advantages of earlier partial weight-bearing time and faster recovery.