Aim: To identify the psychological change process of the registered nurses who worked in the epicenter of the COVID-19 outbreak.Background: The pandemic of COVID-19 has continued to pose an unprecedented threat and challenge to people's health around the world. Nurses are at high risk because they work within the closest proximity to patients. Understanding nurses' psychological change process during the care for patients with COVID-19 is imperative for healthcare leaders.Methods: This was a qualitative descriptive study that took place in a hospital in Wuhan, China, the epicenter of the COVID-19 epidemic, from February 9th to March 15th, 2020. Using purposive sampling, we interviewed 23 nurses. Data were analyzed using Colaizzi's method of data analysis to find, understand, and describe nurses' experiences.Results: The psychological change process of frontline nurses included three stages, early, middle, and later stages. The psychological characteristics of each period were ambivalence, emotional exhaustion, and energy renewal, respectively. Nurse leaders were anchors in facilitating frontline nurses' psychological adaptation.Conclusions: In the past month, the psychological characteristics of nurses changed over time. The study indicated the necessity for nurse leaders to implement intervention programs based on nurses' psychological characteristics in different periods to promote nurses' health during this critical time period.