Palmoplantar pustulosis (PPP) is a stubborn skin disease involving repeated aseptic small pustules on the palms and soles of the feet, which is triggered and exacerbated by metals and dental focal infections. There are few reports of an exacerbation of PPP symptoms after orthognathic surgery. The patient is a 40-year-old female who consulted an orthodontist at our hospital, complaining of a protruding maxilla and malocclusion. Under the diagnosis of skeletal prognathism, she underwent surgery for jaw deformity. Although no allergic symptoms were observed during the orthodontic treatment prior to surgery, postoperative scaling on the palms and soles of her feet worsened, and itching was observed on the skin, especially on the titanium plate used to secure the bone fragments. Under the diagnosis of metal allergy, treatment with steroids and vitamin D ointment failed to improve the condition, so surgery was performed to replace the metal plate with a non-metallic absorbable plate in the third postoperative month. Afterwards, the pruritus resolved, and erythema and scale on the palms and soles nearly disappeared. In the present case, though, oral bacterial infection, a past history of smoking, and stress from surgery were also considered to be possible causes of PPP exacerbation, and we concluded that one of the causes of PPP exacerbation was metal allergy from the plates or screws used to fix the bone fragments.