Treatment of femoral neuropathy caused by iliacus hematoma can be divided according to operative treatment and non-operative treatment. Recently, percutaneous drainage has been more popular because it is relatively simple, convenient, and less invasive. After warfarin overuse, a 71-year-old male patient visited the emergency room with femoral neuropathy caused by a left iliacus muscle hematoma measuring approximately 110×64 mm, 75×60 mm in size on coronal and sagittal computed tomography angiograhy. Without trauma, weakness of the left hip flexor and left knee extensor was noted with strength of 2/5 (poor) each. Immediate medical treatment using vitamin K and fresh frozen plasma was started and percutaneous drainage was performed. Two days after visiting the emergency room, neurological symptoms were improved and non-operative treatment was continued. Twenty four days after being hospitalized, the size of the hematoma was reduced to approximately 75×45 mm, 62×40 mm in size. Approximately three months after hospitalization, most of the hematoma was absorbed. After one year, mild atrphy of quadriceps and mild diffuse pain were noted, however, no other symptoms were observed.