Abstract: [Objective] To investigate the characteristics of postoperative complications of mobile-bearing unicompartmental knee arthroplasty. [Methods] A total of 313 patients (373 knees) who underwent unicompartmental knee arthroplasty in our department from August 2008 to August 2020 were retrospectively analyzed. The characteristics of postoperative complications were followed up. Kaplan Meier survival analysis was performed with total knee arthroplasty as the endpoint. [Results] The 10-year cumulative survival rate of the prosthesis was 91.8%. During the follow-up period, 22 cases (7.0%) occurred complications, including 3 males (13.6%), 19 females (86.4%), 12 bearing dislocation (3.8%), 4 snapping (1.3%), 4 pain (1.3%), 1 aseptic loosening (0.32%) and 1 incision complication (0.32%). Treatment of postoperative complications: 8 cases of exchanging thicker bearing, 1 case of manual reduction, 5 cases of TKA revision, 1 case of incision debridement and suture, 1 case of knee arthroscopic debridement. [Conclusion] The most common complication of mobile-bearing unicompartmental knee arthroplasty was bearing dislocation. For the treatment of postoperative complications, doctors should first clarify the causes and then developed the treatment plan.