© Stem Cell Investigation. All rights reserved.An outbreak of a new coronavirus causing severe respiratory disease (COVID-19) was first reported in China and rapidly spread worldwide. Clinical spectrum changes from asymptomatic infection to severe illness and even death, and no specific treatment is currently available. A range of antiviral, antimalarial and antibiotic agents are being used. We report a case of a COVID-19 patient that progressed to severe disease requiring intubation and intensive care. We performed mesenchymal stem cell (MSC) transplantation considering the signs showing persistent excessive immune response and deterioration despite all supportive and drug therapies. The two rounds of transplantation did not result in any severe complications and was well-tolerated. Clinical signs were improved. The use of MSC therapy may be considered for compassionate use in selected patients.