Background: Jaw cyst is the most common disease of the oral and maxillofacial region. In addition to the pathogenic tooth, the roots of some teeth are often located in the cavity of the cystic capsule. Whether these involved teeth require root canal therapy and apicoectomy is still inconclusive. In the present study, we aimed to preserve the pulp activity of involved teeth in jaw cyst by improved operation.Methods: In our improved surgical method, the root canal therapy was not performed on the involved teeth, and no apical excision was performed during the operation. 63 involved teeth in 20 cases of jaw cyst treated by our department were selected between September 2015 and October 2017. The involved teeth were diagnosed by X-ray, CBCT, and a pulp vitality test before surgery. We observed the pulps' activity in the involved teeth and the efficacy of surgery for 12-36 months.Results: Electrical activity test of 63 involved teeth pulp in 20 patients with jaw cyst was normal or insensitively before operation. The involved teeth were preserved by improved surgical method. After 12-36 months’ follow-up, the pulp activity of 53 involved teeth (84.1%) were preserved, whereas 10 teeth (15.9%) showed adverse symptoms such as redness and swelling in the apical area, fistula, and pain. These symptoms resolved after postoperative root canal therapy. Chewing function was restored well. There was no recurrence and the bone cavity gradually reduced and finally disappeared, and bone density returned to normal after long term follow-up.Conclusion: Our results showed that to preserve the activity of the involved teeth for the treatment of jaw cyst by performing an improved operation method was effective.