Objective To investigate the clinical effects of minihook locking plate fixation for the treatment of avulsion intraarticular fractures of the metacarpophalangeal joint. Methods A retrospective case series study was conducted to analyze the clinical data of 13 patients with avulsion intraarticular fractures of the metacarpophalangeal joint admitted to Beijing Luhe Hospital of Capital Medical University from June 2016 to December 2017. There were nine males and four females, aged 22-61 years［(46.0±1.3)years］. All patients had closed fracture. According to Pechlaner classification, there were 5 patients with Grade A1 and 8 patients with Grade B1. All fractures were treated with open reduction and mini-hook locking plate internal fixation. Operation time, intraoperative blood loss, internal fixation position and bone healing time were recorded. The target joint range of motion (ROM) and grip strength were compared with the contralateral side two months after operation. Hand function was evaluated by total active motion (ATM). Visual analogue scale (VAS) was evaluated before operation two months after operation. Intraoperative and postoperative complications were recorded.  Results All the patients were followed up for 9-19 months［（11.3±1.1）months］. The operation lasted for 20-30 minutes［（25.5±1.3）minutes］, with blood loss of 5-10 ml［（5.5±1.3）ml］. After operation, anatomical reduction was achieved in all patients and position of implant placement was suitable. Bone healing time was 4-8 weeks ［(4.7±0.3)weeks］ for all fractures. There were no significant differences  in the target joint ROM compared with the contralateral side  two months after operation (P>0.05). ATM was excellent in 11 patientsand good in 2, with excellent rate of 100%. VAS was significantly decreased from preoperative (5.9±1.1)points to (0.5±0.1)points two months after operation (P<0.05). No internal fixation failure or wound infection occurred after operation.  Conclusion For avulsion intraarticular fractures of the metacarpophalangeal joint, minihook locking plate internal fixation has advantages of shortened operation time, rigid internal fixation after anatomical reduction, shortened bone healing time, fast recovery of hand function, obvious pain relief and few complications, which provides a treatment alternative for clinics.