Abstract: Objective To compare the clinical outcomes and complications between locking compression plate(LCP) and LCP with fibular allograft(F-LCP) in the treatment of older patients with displaced proximal humerus fracture(PHF). Methods From January 2013 to December 2015, a total of 104 older patients with displaced PHF including three-part or four-part fracture treated in Chinese PLA General Hospital were included in this study. Of the 104 cases, 61 cases were treated with simple LCP fixation as group Ⅰ, while the other 43 cases were treated with LCP combined with allogeneic fibula as group Ⅱ. Group Ⅰ included 14 males and 47 females with an average age of(72.02±8.90) years, and group Ⅱ included 9 males and 34 females with an average age of(72.95±7.76) years. The radiographic indicators and functional outcomes(Constant-Murley scores, DASH scores, UCLA scores,ROM scores and VAS scores) were collected and compared between the two groups before and after surgery. Results There was no statistically significant difference in general data between the two groups at baseline. The fractures healing time was(4.72±0.93)months in group Ⅰ, and(4.77±0.90) months in group Ⅱ, without statistically significant difference. The height loss of humeral heads was(4.48±2.06) mm in group Ⅰ, significantly higher than(2.19±1.58) mm in group Ⅱ(P< 0.001). The change of neckshaft angles in group Ⅰ was also greater than that in group Ⅱ (8.56±4.96)° vs (3.17±2.93)°, P< 0.001). In group Ⅰ, 11 cases developed varus malunion(neck-shaft angle < 110°), 8 cases had screw perforation, and 2 cases had avascular necrosis(AVN). In group Ⅱ, 1 case had screw perforation, 2 cases had avascular necrosis(AVN) and 2 cases had varus malunion. The difference of complication incidence in two groups was statistically significant(34.43% vs 11.63%, P=0.008). There were significant differences in Constant-Murley score, DASH score, UCLA score and ROM score between group Ⅰ and group Ⅱ (62.89±8.25) vs (75.42±4.77),(31.15±9.55) vs (16.09±2.87),(28.97±1.61) vs (31.40±1.50),(18.34±4.43) vs (25.77±3.84), all P< 0.05. However, no significant difference was found in VAS score between two groups (1.57±0.62) vs (1.42±0.55), P=0.189. Conclusion The present study indicates that LCP with fibular allograft has a better functional outcome and a lower complication rate compared to LCP alone for older patients with displaced proximal humerus fractures.