Double‐filtration plasmapheresis is an effective and safe treatment for pemphigus. We retrospectively evaluated the decrease in autoantibody titer and pemphigus disease area index following double‐filtration plasmapheresis in five patients with moderate to severe pemphigus, who were physically and/or serologically unresponsive to 1.0 mg/kg per day of prednisolone and other supportive drugs and ointments. The percentage reduction in autoantibodies 85.6 ± 14.4% (P = 0.00014), and that in pemphigus disease area index was 75.4 ± 24.3% (P = 0.0023). No side‐effects were observed. All patients exhibited clinical improvement after undergoing double‐filtration plasmapheresis, and the prednisolone dose was reduced by 41 ± 8.9 mg (P = 0.0005) approximately 3 months after double‐filtration plasmapheresis. To our knowledge, this is the first report evaluating the efficacy of double‐filtration plasmapheresis with pemphigus disease area index, and it demonstrated that double‐filtration plasmapheresis is a safe “subtracting” treatment for patients with drug‐resistant pemphigus.