Background: Decreased physical activity significantly increases the probability of prevalent metabolic syndrome (MetS) with substantial impact on the expected course of COPD. Objective: Our research aims to assess the metabolic consequences of chronic obstructive pulmonary disease (COPD) and evaluate the prevalence of MetS and its interrelations with age, sex, comorbidities, drug intake, degree of decreased lung function, nutritional status, physical activity and quality of life. Methods: A cross-sectional study was performed on a random sample (n 5 401) at the Department of Pulmonary Rehabilitation of the National Koranyi Institute of Pulmonology from March 1, 2019 to March 1, 2020 in Budapest, Hungary. Anthropometric and respiratory function tests and laboratory parameters of all patients were registered. Results: MetS occurred in 59.1% of COPD patients with significant gender difference (male: 49.7% female: 67.6%). Concerning BMI, the prevalence of MetS was higher with BMI.25 kg m
2 (P < 0.0001). Patients with this syndrome had significantly worse FEV1%pred (43 (30.56) vs. 47 (36.61); P 5 0.028), lower quality of life (CAT: 26 (21.32) vs. 24.5 (19.29); P 5 0.049) and significantly more frequent exacerbations (2 (1.3) vs.1(0-2); P < 0.05), than patients without MetS. The prevalence of comorbidities were higher in overweight/ obese patients (BMI> 25 kg m-2). Conclusions: In COPD patients MetS negatively affect respiratory function and quality of life and promotes exacerbations of the disease. MetS is related to nutritional status and the level of systemic inflammation in COPD patients.  Kulcsszavak: chronic obstructive pulmonary disease, metabolic syndrome, prevalence, inflammation, exacerbations, quality of life