Background: The aim of this study was to investigate the association of socio-economic status (SES) with dysglycemia and the lifestyle-related risk factors, and to analyze to which extent known risk factors explain socio-economic differences in diabetes risk. Methods: Two population-based cross-sectional surveys in Finland including 1696 men and 1946 women aged 45–64 years who participated in a health examination in 2004 or 2007. Dysglycemia was determined by an oral glucose tolerance test. Total type 2 diabetes (including previously known and screen-detected type 2 diabetes), impaired glucose tolerance and impaired fasting glucose formed the category of total dysglycemia. Questionnaires and clinical examination were completed to assess risk factors for dysglycemia. SES was defined by education and household income. Results: In both genders, the prevalence of total dysglycemia differed statistically significantly between educational groups. Low education was statistically significantly associated with higher risk of total type 2 diabetes in women. The household income level was inversely associated with total type 2 diabetes in women and with total dysglycemia in men. Obesity, unhealthy diet and smoking were all inversely related to SES in both men and women. The observed association between education and dysglycemia was slightly attenuated after adjustment for obesity and other risk factors for diabetes. Conclusions: Low education was associated with an increased risk of dysglycemia more strongly than the low household income. Risk factors, especially obesity, explained only partly the observed associations between dysglycemia and education.