As of February 2020, the novel coronavirus disease (COVID-19) outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) started in China in December 2019 has been spreading in many countries over the world.123 The numbers of confirmed cases are increasing over 70,000 including 31 Korean patients as of third week of February 2020. The World Health Organization declared the SARS-CoV-2 outbreak a public health emergency of international concern on January 30, 2020.4 While the information on epidemiologic investigation and clinical manifestation are being accumulated, viral kinetics of the novel virus have not been systematically evaluated yet. To understand the behavior of the virus in human body, we present the viral load kinetics of the first two patients in Korea.