The severe low birth rate and aging population in Korea are foreseen to have a significant effect on the sustainability of society, and health and welfare policies of Korea. In particular, many changes in Korean society by COVID-19 are likely to amplify the ripple effects of demographic changes, such as low birth rate and aging population. Korea's population fluctuations intensified since COVID-19 are expected to develop into a new phase, so that an in-depth study needs to be conducted on the direction after the spread of COVID-19. This study analyzes changes in births, deaths, and population mobility during the spread of COVID-19 to identify the demographic shock by the global pandemic, and to suggest policy directionsfor Korean society to overcome the problems of serious low birth rate and aging population.