Chronic diseases have become a part of the everyday life of modern lifestyle. Systemic lupus erythematosus (SLE), as one of numerous autoimmune chronic diseases, can have a course without significant impact on the patient's daily life, but it can also lead to relapses involving organs, causing disability or life-threatening situations. Health is one of the factors that significantly affect the quality of life. Individual self-assessment of health status and quality of life is an integral part of research related to the assessment of the quality of life of individuals with chronic diseases. The aim of this study was to examine the quality of life in individuals with active and inactive phases of SLE and to compare them due to the duration of the disease. The study included 100 participants with SLE. Quality of life was assessed using the SF-36 questionnaire along with socio-demographic data, data on the duration of the disease, and the disease phase confirmed by an immunorheumatologist during the most recent examination. The results showed that there is a difference in the quality of life’ perception between the active and inactive phases of the disease among examinees. The quality of life of the participants was statistically significantly associated with physical functioning (p=0.011), bodily pain (p=0.001), limitations due to physical difficulties (p=0.004), perception of general health (p=0.017), and social functioning (p=0.009) in relation to disease activity. The quality of life of the participants was not statistically significantly associated with limitations due to emotional difficulties (p=0.091), mental health (p=0.112), and vitality/energy (p=0.138) in relation to disease activity. No statistically significant association was found between any of the examined dimensions of quality of life and the duration of the disease.