To analyze the cause and therapy of hydrops in subcutaneous scalp after repairing skull defect by using silicon-polyester fiber network, a total of 91 patients who were treated with silicon-polyester fiber network to repair skull defect from June 1996 to October 2000 in the Department of Neurosurgery, Nanshan People's Hospital were analyzed retrospectively. And 56 cases of them had hydrops of subcutaneous scalp and treated with suction and pressure dressing, including 11 cases of less than 20 mL hydrop quantity, 27 cases of 20-50 mL, and 18 cases of more than 50 mL. They were observed for 6 weeks averagely after operation and were healed within 4 weeks by simple management. No recurrence of hydrops was found in subcutaneous scalp. It is indicated that silicon-polyester fiber network in repair of skull defect may complicate with hydrops of subcutaneous scalp usually. However, the prognosis will be good by means of drainage, so it can be used as a therapy for skull defect.