Objective: To present a novel method called triplanar chevron osteotomy to treat hallux valgus (HV). Methods: This is a retrospective study. In this study, the CT data of HV patients with painful callosities were evaluated retrospectively between 1 June 2018 and 1 June 2020. CT data from 49 consecutive patients (59 feet) with HV were evaluated. The average age at the time of surgery was 49.6 years (range, 30-63 years). The apex of the chevron osteotomy procedure was located at the center of the first metatarsal and was defined as the line formed by the central point perpendicular to the fourth metatarsal bone. The cut planes of the plantarward oblique chevron osteotomy (POCO) were defined as follows: chevron osteotomy along with 20 of plantarward obliquity. The triplanar osteotomy incision was made using the POCO method, with the direction inclined by 10 distally. The intermetatarsal angle (IMA), the HV angle (HVA), the projection of the second metatarsal (PSM), the metatarsal protrusion index (MPI), and the metatarsal protrusion distance (MPD) were all calculated before and after the operations. The length of the first metatarsal was measured and calculated with an equation. Results: The results showed that the HVA was significantly decreased after surgery (32.7 AE 4.6 vs 14.9 AE 2.1 , t = 25.583, P < 0.001) in the triplanar, traditional, and POCO groups. The IMA was also significantly decreased (14.7 AE 2.0) compared with the results before surgery (8.0 AE 1.1 , t = 22.739, P < 0.001) in these groups. Compared with traditional osteotomy and POCO, there were no differences in correcting deformities on axial planes for the HVA (14.5