PURPOSE: Lymphocutaneous fistula after lymph node dissection is intractable, yet there is no established treatment strategy. This study demonstrates the wound closure time achieved by a new method of combined internal and external negative pressure wound therapy (CIEN) in patients with lymphocutaneous fistula. METHODS: The subjects of this study were six consecutive patients with lymphocutaneous fistula after lymphatic surgery, who were treated with CIEN between 2018 and 2020. The CIEN technique can be summarized as follows: first, internal foam is inserted into the fistula from the opening of the fenestration. Next, a slightly larger area of external foam is applied above the fistula flap outside the external margin of the foam-filled fistula. After bridging the internal foam and external foam, negative-pressure wound therapy is carried out on this bridging foam block. RESULTS: CIEN led to rapid and complete wound healing in all six patients. Fistula flap margin ischemia developed in one patient, but adjusting the mode and pressure settings resulted in improvement. Three patients suffered contact dermatitis. There were no signs of tumor or fistula recurrence in any patients after at least 3 months of follow-up. CONCLUSION: CIEN is an effective and less invasive treatment modality than the conventional method of managing lymphocutaneous fistula.