The COVID-19 outbreak has not only posed a threat to physical health but has also changed our daily lives. This study explored how the COVID-19 pandemic affected Korean parents’ and children’s daily lives and stress levels. Parents’ childcare time, children’s screen time, the time spent for social interactions and learning, and parents’ and children’s stress levels before and after the pandemic were compared. The main caregivers’ childcare time increased significantly during the pandemic (4.00 h/day). For children, the time spent for screen time (1.76 h) and online interactions (0.95 h) increased significantly, whereas face-to-face interaction time (4.17 h) and time spent learning (2.16 h) decreased significantly. In addition, parents’ and children’s stress levels increased significantly during the pandemic. Other descriptive information is provided and discussed. Our results indicate that Korean parents and children experienced significant disruption to their daily lives and increased stress during the pandemic.