Purpose: We report a case that iatrogenic dorsiflexion deformity after hallux valgus surgery treated successfully with crescenteric plantar flexion metatarsal osteotomy. Materials and Methods: 43 years old female who suffered from left fore foot pain and deformity after hallux valgus surgery was evaluated. Results: Preoperatively she did not put on ordinary shoes and had had persistent pain and discomfort on 1st metatarsal area. She also had a callus on plantar surface of 2nd metatarsal head. Simple AP and Lateral x-ray identified that 1st metatarsal bone had a 23 degree dorsiflexion deformity. For correction of deformity, plantarflexion crescenteric osteotomy was performed on proximal 1st metatarsal area. After operation, All of symptom eliciting patient was gone and 43 points of AOFAS scale preoperatively improve 100 points and the patient very satisfied. Post operative x-ray was showing complete correction of deformity. Conclusion: As a treatment of iatrogenic dorsiflexion deformity after hallux valgus surgery, the crescenteric plantar flexion osteotomy can be good and safe modality for correction.