Background Anxiety, depression and perceived stress are risk factors for adverse health problems. Inflammation participates in the development of chronic diseases such as psychiatric disorders. This study explored the relationships between inflammatory biomarkers and depression, anxiety and perceived stress in an obese adult population. Methods The relationships between psychological scores and inflammatory markers were analyzed. Results A higher BMI was not correlated with a higher anxiety score (P=0.152); however, BMI was positively associated with a higher depression score (P<0.001) and a higher perceived stress score (P<0.001). Multivariate linear regression analysis revealed that in participants with BMI≥30 and 25≤BMI<30, depression and perceived stress were significantly and independently associated with ICAM-1, E-selectin and CRP, but these associations were not observed in participants with BMI<25. The anxiety score was not associated with any inflammatory marker in any group of subjects, as determined by multivariate analysis. Conclusion Depression and perceived stress were strongly associated with increased serum levels of pro-inflammatory markers, including ICAM-1, E-selectin and CRP, among a general obese population from the United States. These results further suggest that depression and perceived stress might also be chronic systemic inflammatory diseases.