[Objective] To explore the clinical consequences of double mini plates for internal fixation of ulnar and radial shaft frac- tures. [Methods] A retrospective study was done on 16 patients who received open reduction and internal fixation (ORIF) of ulnar and radial shaft fractures with double mini plate (the metacarpal plate) in our department from March 2019 to March 2021. The clinical and radiograph- ic documents were evaluated. [Results] All the patients had ORIF completed successfully, with no serious intraoperative complications, and followed up for a mean of (19.4±3.2) months. The supernation and pronation range of motions (ROMs) significantly increased, additionally, the DASH score, Grace and Eversmann scale significantly improved at 6 months compared with those at 3 months postoperatively (P＜0.05) , with excellent rate of 100% in term of Grace and Eversmann scale at 6 months. By the time of the latest follow up, fracture healing achieved in all the patients without implant loosening or breaking. [Conclusion] The double metacarpal plates are feasible and effective for internal fixation of ulnar and radial shaft fractures, with advantages of less occupation and minimizing intervention of local blood supply.