Background: Depression, which is the most common psychological disorder among patients with end-stage renal disease (ESRD), is commonly associated with poor oral intake which can aggravate anemia and malnutrition in chronic dialysis patients. The objective of this study is to explore the association between depression and C-reactive protein (CRP), ferritin, serum albumin and hemoglobin/hematocrit in patients with chronic kidney disease (CKD) and ESRD. Methods: Sixty-eight patients on hemodialysis (HD), 47 patients on continuous ambulatory peritoneal dialysis (CAPD) and 26 patients with CKD on conservative management were enrolled in this study. All patients were evaluated for the presence of depression using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) Axis I Disorders-Clinician Version (SCID-CV). The severity of depression was evaluated by means of the Beck Depression Inventory (BDI). Serum CRP (nephelometric method), ferritin (immunometric method), albumin (bromcresol green technique), hemoglobin, and hematocrit levels were measured. Results: A total of 34 of 141 patients (24.1%) had depression. The mean BDI score was higher in depressive patients compared to nondepressive patients. In HD patients the frequency of depression and CRP and ferritin levels were higher than in other groups. Patients with depression had lower hemoglobin, hematocrit and serum albumin levels and higher CRP and ferritin levels than patients without depression. The BDI score showed a positive correlation with serum CRP and ferritin levels, but a negative correlation with the serum albumin level. Conclusions: We observed that CKD and ESRD patients with anemia, hypoalbuminemia and higher serum CRP and ferritin concentrations should be evaluated for depression after potential somatic causes have been eliminated.