Objective: We examined a possible association between hematological parameters and prediabetes (isolated impaired fasting glucose, isolated impaired glucose tolerance, and combined impaired fasting glucose/impaired glucose tolerance) as well as newly diagnosed and known diabetes in 32-81year old men and women from the general population. Methods: This cross-sectional analysis was based on 2,963 participants of the Cooperative Health Research in the Region of Augsburg F4 Study conducted in 2006-2008 in Southern Germany. Hematological parameters were determined using impedance measurements. Results: In multivariable multinomial regression analysis hemoglobin levels were significantly associated with isolated impaired glucose tolerance and combined impaired fasting glucose/impaired glucose tolerance compared to persons with normal glucose tolerance (Odds Ratio per standard deviation increment: 1.37 for isolated impaired glucose tolerance, and 1.63 for combined impaired fasting glucose/impaired glucose tolerance). Hematocrit values were significantly associated with isolated impaired glucose tolerance, combined impaired fasting glucose/impaired glucose tolerance, and newly diagnosed diabetes (Odds Ratio per standard deviation increment: 1.33 for isolated impaired glucose tolerance, 1.48 for combined impaired fasting glucose/impaired glucose tolerance, and 1.29 for newly diagnosed diabetes). White blood cell count showed a significant association with isolated impaired glucose tolerance (Odds Ratio per standard deviation increment 1.46; 95% confidence interval 1.27-1.66), newly diagnosed diabetes (Odds Ratio 1.55; 95% confidence interval 1.31-1.83), and known diabetes (Odds Ratio 1.43; 95% confidence interval 1.23-1.66). While we found no association between platelet count and prediabetes or diabetes, mean platelet volume was significantly related to known diabetes (Odds Ratio per standard deviation increment 1.19; 95% confidence interval 1.02-1.38). Most associations were more pronounced in women than men. Conclusion: Clinically relevant hematological parameters may play a role in the early development of type 2 diabetes. Further research is necessary to study the gender-specific contribution of hematological parameters to the pathogenesis of prediabetic states and finally to the manifestation of type 2 diabetes.