Objective: Gypsies (or Roma) recently experienced a transition from a traditional to a Westernized lifestyle. Although mortality in this population is 4-fold higher compared with non-Gypsies, very limited information is available on their morbidity especially with regard to non-communicable diseases. Our aim was to determine the prevalence of type 2 diabetes mellitus (T2DM), metabolic syndrome and cardiovascular diseases in Gypsies and non-Gypsies living in the same region of southern Slovakia. Materials and methods: We examined 156 Gypsies and 501 non-Gypsies who participated in a population survey. Age- and sex-standardized prevalence rates were computed for each of the following: T2DM, obesity, hyperlipidemia, hypertension, hyperinsulinemia, elevated albumin/creatinine ratio (ACR), metabolic syndrome and cardiovascular disease. Results: Age–sex standardized prevalence of T2DM was 30% (95% CI=22–39) in Gypsies and 10% (8–13, P=0.0001 for comparison of ethnic groups) in non-Gypsies. Corresponding prevalence of the other variables are: 65% (56–74) and 30% (26–34, P=0.0001) for obesity, 69% (61–76) and 59% (54–63, P=0.04) for hypercholesterolemia, 66% (59–74) and 39% (35–43, P=0.009) for hypertriglyceridemia, 49% (42–56) and 43% (39–47, P=0.1) for hypertension, 33% (26–50) and 8% (2–14, P=0.002) for hyperinsulinemia, 16% (9–22) and 5% (3–7, P=0.0001) for elevated ACR, 20% (12–27) and 4% (3–6, P=0.0001) for metabolic syndrome and 35% (28–43) and 26% (22–29, P=0.004) for cardiovascular disease. Conclusions: Compared with non-Gypsies, Gypsies had a much higher prevalence of T2DM, metabolic syndrome and cardiovascular disease, which may contribute to their higher mortality.