Insulin resistance (IR) is present long before the onset of type 2 diabetes and results not only from inherited and lifestyle factors but likely also from environmental conditions. We investigated the association between modelled long-term exposure to air pollution at residence and biomarkers related to IR, subclinical inflammation and adipokines.Data was based on 2,944 participants of the KORA (Cooperative Health Research in the Region Augsburg) F4 study conducted in southern Germany (2006-2008). We analysed associations between individual air pollution concentration estimated by land use regression and HOMA-IR, glucose, insulin, HbA1c, leptin, and hs-CRP from fasting samples using multivariable linear regression models. Effect estimates were calculated for the whole study population and subgroups of non-diabetic, pre-diabetic and diabetic individuals.Among all participants, a 7.9μg/m(3) increment in particulate matter <10μm was associated with higher HOMA-IR (15.6% [95%-CI: 4.0;28.6]) and insulin (14.5% [3.6;26.5]).Nitrogen dioxide was associated with HOMA-IR, glucose, insulin, and leptin. Effect estimates for pre-diabetic individuals were much larger and highly statistically significant, while non-diabetic and diabetic individuals showed rather weak associations. No association was seen for HbA1cOur results suggested an association between long-term exposure to air pollution and IR in the general population mainly attributable to pre-diabetic individuals.