Objective To investigate the effectiveness of a novel lateral tibial plateau annular plate (hereinafter referred to as the novel plate) fixation via fibular neck osteotomy approach for posterolateral tibial plateau fractures. Methods Between January 2015 and December 2018, 22 patients with posterolateral tibial plateau fractures were treated. There were 10 males and 12 females with an average age of 39.0 years (range, 25-56 years). Seven fractures were caused by falls, 10 by traffic accidents, and 5 by falling from height. The time from injury to hospitalization ranged from 3 to 12 days, with an average of 7.0 days. All patients were closed fractures. According to Schatzker classification, the fractures were classified as type Ⅱ in 8 cases, type Ⅲ in 9 cases, type Ⅴ in 1 case, and type Ⅵ in 4 cases. The fractures were fixed with the novel plates after reduction via fibular neck osteotomy approach. The fracture reduction and healing were observed by X-ray film after operation. The range of motion of the knee joint was recorded and the function was evaluated by modified American Hospital for Special Surgery (HSS) score. Results All operations were completed successfully. The operation time was 60-95 minutes (mean, 77.6 minutes). The intraoperative blood loss was 100-520 mL (mean, 214.5 mL). There was 1 case of common peroneal nerve injury during operation and 2 cases of fat liquefaction of incision after operation. All patients were followed up 13-32 months (mean, 19.4 months). Postoperative X-ray films showed that the fracture reduction was good in 17 cases and moderate in 5 cases, and all fractures healed with a healing time of 10-18 weeks (mean, 13.0 weeks). At last follow-up, the range of motion of the knee joint ranged from 100° to 145° in flexion (mean, 125.5°) and from 0° to 4° in extension (mean, 1.2°). The modified HSS score was 82-95 (mean, 86.3). There was no complications such as plate deformation, screw fracture, fracture reduction loss, skin necrosis, and so on. Conclusion For posterolateral tibial plateau fractures, the novel plate fixation via fibular neck osteotomy approach has the advantages of clear intraoperative field, firm fracture fixation, and less postoperative complications, which is beneficial to the recovery of knee joint function.