The novel coronavirus disease 2019 (COVID-19) is spreading in Japan. We have collected a total of 26 patients with COVID-19 who required extracorporeal membranous oxygenation (ECMO). The available data from the first 14 cases demonstrated that the median age of patients was 71 and the median PaO₂/FIO₂ ratio, positive end-expiratory pressure, mean airway pressure, and lung compliance were 70, 15 cmH₂O, 21 cmH₂O, and 28 mL/cmH₂O, respectively. Median serum KL-6 level was 333 U/mL. Consequently, 16 (62%) out of the 26 have been weaned off and 6 (26%) have been extubated and on rehabilitation, while the other 10 (38%) remain on ECMO. There seemed to be two phenotypes of COVID-19: one with impaired lung compliance and one with preserved lung compliance. The latter phenotype was likely to be favored from the use of ECMO. Further investigation is necessary to clasrify the optimal use of ECMO in patients with COVID-19.