To overcome coronavirus disease 2019 (COVID-19), it is essential to develop a therapeutic drug. For that purpose, an excellent in vitro model that can be used for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research is needed. It is desired to use a physiologically relevant model rather than a cancer cell line such as Vero cell, which is widely used in SARS-CoV-2 research. We have conducted SARS-CoV-2 research using (1) organoids and (2) organ-on-a-chips. (1) We are trying to clarify the mechanism of SARS-CoV-2 infection using airway organoids. Among various airway epithelial cells, ciliated cells can be easily infected. On the other hand, basal cells, which are stem cells in the airway, cannot be infected with SARS-CoV-2. We confirmed that basal cells that survive after the viral infection can repair damaged airways. (2) Using an organ-on-a-chip that can reproduce the epithelial-endothelial barrier, we are investigating the mechanism by which SARS-CoV-2 destroys the biological barrier. SARS-CoV-2 infects epithelial cells but not endothelial cells. We confirmed that infected epithelial cells secrete interferons (IFN), and then enhance the vascular permeability. Currently, we are trying to develop a therapeutic drug using our organoids and organ-on-a-chip.