Recently, Professor Guo Xueli from the second vascular surgery department of our hospital successfully operated on a 15-month-old child with congenital arteriovenous fistula, which is the youngest patient with congenital arteriovenous fistula treated by our hospital and the smallest patient with congenital arteriovenous fistula reported in China. Wang Yanjun, a child from the Department of Vascular Surgery of the First Affiliated Hospital of Zhengzhou University, was found to have tremor in the right inguinal region and thickening of the proximal femoral limb at the age of 4 months, and no significant abnormality was found on vascular ultrasound examination at the local hospital. Recently, the above symptoms of the child’s right lower extremity further aggravated and swelling of the affected extremity appeared, and the child’s family was very worried, but where to seek medical treatment also made them brain-damaged. Later, they learned from the Internet that there was a peripheral vascular disease specialist in the Department of Vascular Surgery of the First Affiliated Hospital of Zheng University, and came to our hospital by name. In the outpatient clinic, Dr. Zhang found that the child’s right inguinal tremor was obvious, and he considered it to be an arteriovenous fistula, and reported it to Prof. Guo Xueli immediately because of the child’s young age and complexity. The child was diagnosed with “congenital arteriovenous fistula of the right lower extremity” and was admitted with abnormal blood flow between the right common femoral artery near the bifurcation and the vein after an ultrasound examination. After admission, the arteriogram of the lower extremity was further improved, showing abnormal blood flow between the arteries and veins at the near bifurcation of the right common femoral artery, and arteriovenous fistula was considered. The next challenge was to determine which treatment modality should be used for the child. At this stage, the child had already shown symptoms of enlargement and growth of the affected limb compared to the opposite side, and the child was still young, so if the treatment was not complete, the growth and development of the affected limb would be affected for the rest of the child’s life. On June 29, Prof. Guo Xueli led doctors Zhang Chong, Chen Ningheng, and Wang Yanjun to perform the surgery on the child. This suggests that the fistula may be located in the deep femoral artery and its branches. In general, the most obvious location of the tremor is where the fistula is located, but in this child, multiple obvious tremors could be palpated in the region of the deep femoral artery and its branches, and the development of the deep femoral artery was easily normal, which made the search for the fistula difficult. The fistula was finally identified as a branch of the deep femoral artery by alternating proximal and distal blockade. After careful freeing of the most pronounced tremor, a huge fistula with a diameter of about 5 mm and a length of about 2 mm was found between the deep femoral artery and the femoral vein, which only allowed the tip of a striated clamp to pass. On the postoperative day, the child did not have any tremor in the inguinal region, the swelling of the affected limb basically disappeared, and the pulsation of the dorsalis pedis artery was normal. Prof. Guo Xueli said that this case was cured after surgery because there was only one fistula branch. Congenital arteriovenous fistula (CAVF) can occur in any part of the body, with the extremities being the most common. The signs include thickening and growth of the limb, vascular murmur, tremor and venous pulsation, skin pigmentation, ulceration, gangrene and muscle atrophy; although CAVF is a benign lesion, it has some biological characteristics of malignant tumors, and the lesion spreads and develops without any tendency of self-healing; at this stage, the treatment for CAVF mainly includes surgery, embolization and combined surgery and embolization; regardless of the treatment method, if it cannot be completely treated, it can be cured after surgery. No matter what treatment method is used, if the fistula is not completely ligated and the diffuse lesion is not removed, it will easily cause the lesion to recur and the symptoms to reappear. In recent years, the second ward of vascular surgery in our hospital, after continuous research and attempts, has accumulated more than ten cases of congenital arteriovenous fistula, and several of them have achieved good results, which has brought hope for the treatment of congenital arteriovenous fistula patients.