Objective  To investigate the clinical effect of treatment of valgus impacted proximal humeral fracture in elderly patients with locking plate internal fixation through deltoid approach.  Methods  A retrospective case series study was carried out to analyze the clinical data of 25 elderly patients with valgus impacted proximal humeral fracture hospitalized in Central Theater General Hospital of PLA from September 2016 to March 2018, including 7 males and 18 females, aged 60-81 years ［(67.9±9.1)years］.According to Neer classification, 21 patients were with three part proximal humeral fracture and 4 with four part fracture. All patients were treated by internal fixation with locking plate through deltoid approach. Rehabilitation exercise training was done after operation. Total length of incision, operation time, intraoperative bleeding volume and fracture healing were recorded. At the last follow-up, the range of motion and abductor muscle strength of the shoulder joint between the affected side and the healthy side were compared, joint function was evaluated using the ConstantMurley score, and the postoperative complications were observed.  Results  All patients were followed up for 12-23 months ［(14.6±3.2)months］.Total length of incision was 6.4-8.8 cm ［(7.1±1.2)cm］. Operation time was 68-106 minutes［(84. 0±5.6)minutes］. Intraoperative bleeding volume was 55-95 ml ［(62.5±16.4)ml］. All the fracture lines were well reduced and bony union was observed in all patients at popstoperative 6 months. At the last follow-up, there was no significant difference in flexion, abduction, pronation range and abductor muscle strength between the affected side and the healthy side (P<0.05). At the last follow-up, the ConstantMurley score of shoulder joint function was excellent in 9 patients, good in 13, fair in 3, with excellent and good rate of 88%. There was no subacromial impact, humeral head necrosis or other complications after operation.    Conclusion  Locking plate through deltoid approach in treatment of valgus impacted proximal humeral fracture in the elderly has the advantages of less operative trauma, shorter operative time, less intraoperative bleeding, less postoperative complications, good reduction of fracture and good functional recovery of shoulder joint.