The skin covering a digital mucous cyst is often very thin and is often excised with the cyst. Thus, transfer of a skin flap is needed for the defect. We have developed a proximal nail fold flap technique by which the thin skin covering the cyst can be preserved. We conducted a retrospective study to assess the effectiveness and reliability of this technique for digital mucous cyst excision. The study group comprised 26 patients treated for 28 digital mucous cysts. The flap was elevated on the nail matrix to expose the distal interphalangeal joint capsule. To preserve the skin in cases in which the skin covering the cyst was exceptionally thin, we did not excise the upper part of the cyst wall. Excision of the cyst and stalk was successful in all cases. Additional excision of the joint capsule or osteophyte(s) was achieved in 20 cases and 5 cases, respectively. No flap necrosis, skin defect or nail deformity resulted. Three of the cysts recurred and were treated successfully by reoperation involving the same flap elevation technique. We conclude that the proximal nail fold flap is useful for excision and reliable for wound coverage after digital mucous cyst excision. J. Med. Invest. 63: 278-280, August, 2016