Objective: In this case report, we present a case wherein we observed a blocking of lymphatic vessels in indocyanine green lymphography and found a shrunken lymphatic vessel intraoperatively. Methods: We performed indocyanine green lymphography and lymphaticovenous anastomosis on a 77-year-old woman. She had previously undergone right mastectomy and axillary lymph node dissection accompanied by radiotherapy and chemotherapy for right breast cancer. She noticed swelling in the right upper limb 22 years after the surgery and consulted our hospital. Although she started wearing elastic sleeve, there was still stiffness in the right upper limb, and we decided to perform lymphaticovenous anastomosis 5 months after the first consultation. Results: In the preoperative indocyanine green lymphography, we observed a linear pattern in the medial side of the right forearm, which suddenly blocked in the middle of the forearm. At that point, we observed dilated lymphatic vessels that were suddenly shrunken at the proximal side intraoperatively. We performed lymphaticovenous anastomosis with the dilated part of this lymphatic vessel. We also performed 4 additional lymphaticovenous anastomoses. The operation time was 2 hours 10 minutes, and the amount of bleeding was minimal. The right upper limb of the patient got softer, and she was satisfied with the result 3 months after the operation. The average circumference change at the 5 points in the right upper limb was −1.26 cm (range, −2.3 to −0.3 cm). Conclusions: There was a possibility that the blocking of the lymphatic vessels was a cause of lymphedema in the upper extremity.