To determine the relationship between nurse burnout, missed nursing care, and care quality following the COVID-19 pandemic. Quality of care and missed nursing care can be consequences of nurse burnout. Little is known about how these factors related to nurse burnout following the COVID-19 pandemic. This study used a cross-sectional correlational design and was conducted in 12 general hospitals across Thailand from August to October 2022. 394 nurses providing direct nursing care to patients during the COVID-19 pandemic completed the survey. The Emotional Exhaustion (EE) subscale of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS), MISSCARE survey, and quality of care reported by nurses were used to collect data. Descriptive statistics and logistic regression models were used to analyse the data. Approximately thirty-six percent of nurses had burnout following the COVID-19 pandemic. Missed nursing care was higher among nurses with burnout. Most participants reported illness/symptoms such as anxiety, fatigue, a lack of concentration, and sleeping problems. After adjusting for demographic characteristics, every additional unit of emotional exhaustion was associated with 1.61 times higher odds of missed nursing care, 3.37 times higher odds of poor quality of nurse care, and 2.62 times higher odds of poor quality of care for the overall unit. The study findings demonstrate that burnout is associated with missed nursing care and poor quality of care following the COVID-19 pandemic. Policymakers, hospital administrators, and nurse managers should invest in strategies to reduce nurse burnout, which can increase patient safety and quality of care.