BACKGROUND The purpose of this retrospective study was to evaluate the clinical and radiological results of hallux valgus surgery using a plantar locking plate. METHODS Proximal oblique metatarsal osteotomy combined with distal soft tissue treatment was performed in 59 adult patients (68 feet) with hallux valgus, using an anatomically pre-contoured plantar locking plate for fixation of the osteotomy. The median age was 64.0 years and the median follow-up period was 16.5 months. RESULTS The mean JSSF scale improved significantly from 56.0 points preoperatively to 95.8 points postoperatively. The mean intermetatarsal angle and hallux valgus angle decreased from 16.4° and 41.8° preoperatively to 4.2° and 10.8° postoperatively, respectively. The mean inclination angle was 19.9° preoperatively and 20.5° postoperatively. Removal of hardware was needed in 2 feet (2.9%). CONCLUSIONS Proximal oblique metatarsal osteotomy is an effective method for relief of pain and improvement of function in correction of hallux valgus deformity. Use of a plantar locking plate provides sufficient maintenance of the correction, and complications associated with the hardware are rare.