Background: The quality of an individual's life consists of the harmony of physical and mental health, which is influenced by working and material conditions and the social environment. Healthcare professionals face a lot of pressure caused by workload. Psychological pressure, lack of health personnel, and shift and overtime work lead to stress and burnout syndrome. Aim: This paper examines the impact of stress and burnout on the quality of life of healthcare workers during the COVID-19 pandemic. Methods: This cross-sectional study was conducted with 105 subjects who worked at the COVID wards at the COVID-19 Respiratory Centre of the University Hospital Centre Rijeka. Results: This research shows that healthcare workers developed symptoms of stress and experienced a high degree of burnout during the COVID-19 pandemic. A small number of healthcare professionals also experienced a worse quality of life. Conclusion: The COVID-19 pandemic put health workers under tremendous psychological pressure. In addition to numerous challenges such as work overload, long working hours, and impacts to work organization; health professionals had to deal with fear, uncertainty, high mortality rates, and the increased use of protective equipment. This impacted the quality of life for at least a small number of health workers.