Objective To investigate and evaluate prevention and treatment of seroma by transposition of tissue flaps and Arista hemostatic powder after regional lymph node resection in patients with malignant tumors. Methods Twelve patients (6 males, 6 females; aged 31-81 years, with metastatic tumors underwent prevention and treatment of seroma with the tissue flaps and Arista hemostatic powder spray after regional lymph node resection. The metastatic tumors involved the axilla in 1 patient with breast carcinoma, the iliac and inguinal regions in 2 patients with carcinomas of theuterine cervix and the rectum, and the inguinal region in 9 patients, including4 patients with malignant fibrous histiocytoma（3 in the thigh, 1 in the leg）,2 patients with squamous carcinomas in the leg, 1 patient with synovial sarcomain the knee, 1 patient with epithelioid sarcoma in the leg, and 1 patient with malignant melanoma in the foot. As for the lymph node removal therapy. 1 patientunderwent axillary lymph node removal, 2 palients underwent lymph node removal in theiliac and inguinal regions, and 9 patients underwent lymph node removal inthe inguinal region. Meanwhile, of the 12 patients, 6 patients underwent transpostion of sartourius flaps with Arista hemostatic powder, 3 patients underwent transposition of the rectus abdominis myocutaneous flaps (including 2 patients treatedwith Arista spray befor the wound closure and 1 patient treated by transposition of local skin flaps with Arista spray used again),and 3 patients underwent only the suturing of the wounds combined with Arista. At the same time, of the 12 patients,only 4 patient underwent the transplantation of artificial blood vessels. Results The follow-up for 2-10 months after operation revealed that 10 patients, who had received the transposition of tissue flaps and the spray of Arista hemostatic powder, had the first intention of the incision heal with seroma cured. Nine patients were given a preventive use of Arista hemostaticpowder and therefore no seroma developed. The combined use of the transpositionof tissue flaps and Arista hemostatic powder spray achieved a success rate of 100% in the prevention or treatment of seroma. However, 1 patient developed microcirculation disturbance 24 hours after operation and underwent disarticulation of the hip; 1 patient developed pelvic cavity hydrops and died 10 months after operation. Conclusion The combined use of transposition of tissue flaps and Arista hemostatic powder spray can effectively prevent or treat seroma after regional lymph node removal in a patient with malignant tumor.