COVID-19 was first detected in Wuhan, China, in December 2019 and spread rapidly in many other countries. This situation, defined now as a pandemic, has turned into a worldwide public health problem that threatens health security, especially that of healthcare professionals. Nurses, particularly those at the forefront of healthcare and directly involved in COVID-19 patient care, have been affected not only physically but also mentally. Because nurses have longer communication and interaction times with patients, they are more concerned about becoming infected or infecting others. Nurses have the highest level of occupational stress compared to other groups and are accordingly subjected to anxiety and depression. For many reasons such as intense working hours, working in a shift system, an insufficient number of personnel, severe conditions of the unit, being in constant contact with patients and their relatives and showing intense empathy for them, nurses experience primary and secondary traumatic stress, job burnout, compassion fatigue, and moral injuries. For this reason, conducting appropriate prevention activities and planning prevention strategies for future pandemic situations is important to support nurses psychologically and to protect their mental health.