To investigate the clinical effects of free descending branch tissue flap of lateral circumflex femoral artery in repairing Wagner grade 3 or 4 diabetic foot wounds. A retrospective observational study was conducted. From October 2019 to January 2022, 12 patients (10 males and 2 females, aged 38-66 years, with an average of 52 years) with diabetic foot wounds who met the inclusion criteria were admitted to the First People's Hospital of Yulin, of whom 5 cases being Wagner grade 3 and 7 cases being Wagner grade 4. Wound debridement and vacuum sealing drainage were performed to control infection, and the wound area after debridement was between 13 cm×6 cm and 28 cm×11 cm. The wounds were repaired with free descending branch tissue flaps of lateral circumflex femoral artery. Among them, the wounds of 4 cases were repaired with single flap of musculocutaneous branch or intermuscular branch of descending branch tissue flap of lateral circumflex femoral artery, 1 case with lobulated flap, 1 case with bilateral tandem flap, and 6 cases with chimeric lateral femoral muscle flap. The area of resected tissue flap was 9 cm×7 cm to 21 cm×10 cm; end-to-end anastomosis was selected between vessels in the donor sites and the recipient sites, and pressurized treatment should be performed if necessary. The donor site wounds of 10 patients were treated with cosmetic tension-relieving suture, and the donor site wounds of 2 patients were repaired with split-thickness skin graft from head. After operation, the condition of wound repair was recorded. After wound healing, the level of 2-hour postprandial blood glucose of patients was measured. During follow-up, the wound healing of the recipient site and scar formation of the donor site were observed. Before and 6 months after operation, computer tomography angiography was used to detect and compare the blood perfusion of the affected limb. At the last follow-up, the walking ability of the patients was recorded. The wounds of 9 patients healed well after operation; the flaps in the recipient site of 2 patients were infected on postoperative day 5 after surgery and were repaired by suturing in stage Ⅱ after open drainage and inflammation control; the distal end of the grafted tandem flap in 1 patient gradually developed purple necrosis on postoperative day 4 and was repaired with a skin graft after debridement. After wound healing, the 2-hour postprandial blood glucose value of all patients was controlled in the range of 8-12 mmol/L. During Follow-up of 6 months to 1 year, 3 patients had partial ulceration in the plantar compression area, which healed after decompression combined with dressing change or flap repair, while the other 9 patients had no ulceration in the recipient area; the appearance of the affected foot was plump after wound healing, the transplanted flaps had good blood supply and good fit with the surrounding tissue, and were wear-resistant, but insensitive. During follow-up, only linear scar remained in the donor area of direct suture in 10 cases, and the skin grafts in the donor area were completely survived in 2 cases. Compared with the patency of the main blood vessels of the ankle joint segment of the affected limb before operation, the vascular network of the flap transplantation area in the affected foot was formed 6 months after operation. At the last follow-up, 8 patients could walk independently, and 4 patients could walk with crutches. The free descending branch tissue flap of lateral circumflex femoral artery is effective in repairing Wagner grade 3 or 4 diabetic foot wounds, which can shorten the course of disease and improve local blood flow.