Objective To investigate the clinical effect of staged repair strategy for chronic sacrococcygeal radiation ulcer. Methods The retrospective cohort study method was applied. Twelve patients with chronic sacrococcygeal radiation ulcer were admitted to Beijing Jishuitan Hospital from January 2010 to June 2020, including 7 males and 5 females, aged 38-74 years. The thorough debridement was performed in the first stage, with wounds area after debridement ranging from 8 cm×6 cm to 22 cm×14 cm, and continuous vacuum sealing drainage (VSD) was performed after the debridement operation. In the second stage, personalized surgery scheme was formulated according to the patient's age, systemic condition, vascular condition, and the position, size, and depth of wound. Six cases were reconstructed with superior/inferior gluteal artery perforator flaps, 4 cases were repaired with gluteus maximus myocutaneous flaps, 1 case was repaired with pedicled latissimus dorsi myocutaneous flap, and 1 case was reconstructed with free transplantation of latissimus dorsi myocutaneous flap. The area of flaps or myocutaneous flaps ranged from 10 cm×8 cm to 25 cm×18 cm. Donor sites of the flaps were sutured primarily in 9 patients and in the other 3 patients were repaired with intermediate split-thickness skin graft in back. The survival of flap or myocutaneous flap after operation, recurrence of tumor, and the appearance and texture of flap or myocutaneous flap, and wound healing were observed during follow-up. Results Flaps or myocutaneous flaps in 11 patients survived after operation, and superior gluteal artery perforator flap in 1 patient had partial distal necrosis, which was covered again with flap pushed to the distal after debridement and resection of the necrotic tissue. The wounds in 8 patients achieved primary healing, 1 patient repaired with superior gluteal artery perforator flap experienced subcutaneous infection, 1 patient repaired with superior gluteal artery perforator flap suffered distal venous congestion of the flap, and 1 patient repaired with gluteus maximus myocutaneous flap had hematoma under myocutaneous flap, and 1 patient repaired with retrograde latissimus dorsi myocutaneous flap had incision exudation and dehiscence, which were all healed after dressing change, etc. There was no recurrence of tumor after the operation. The wounds healed well during follow-up of 2-52 months after discharge, with no recurrence of infection, and the flaps were soft in texture, with satisfactory appearance and well healed donor sites. Conclusions On the basis of thorough debridement and VSD in the first stage, superior/inferior gluteal artery perforator flap, gluteus maximus myocutaneous flap, or pedicled/free latissimus dorsi myocutaneous flap with abundant blood supply is applied to repair chronic sacrococcygeal radiation ulcer in the second stage. The staged operation is reliable, with minimal injury to the donor site of flap and satisfactory therapeutic effect.