Background: Recent studies have reported significant associations between vitamin D deficiency and depression in the general population. Even though both vitamin D deficiency and depression are common in patients with chronic kidney disease (CKD), the association between these two prevalent factors remains poorly elucidated. Therefore, we investigated the association between vitamin D deficiency and depression in CKD patients. Methods: The data from Korean National Health and Nutritional Examination Survey between 2010 and 2012 were used for analysis. Patients with estimated glomerular filtration rate ≤60 mL/min/1.73m2 were enrolled. Vitamin D deficiency was defined as 25-hydroxyvitamin D3 [25(OH)D3] levels ≤10 ng/mL. The patients were divided into groups with or without vitamin D deficiency. Depression was determined by the EuroQOL-5D (EQ5D) questionnaire. Independent associations between vitamin D deficiency and depression were evaluated by multiple logistic regression analysis. Results: The mean age was 71.2±9.3 years, and 257 patients (51.9%) were female. The mean 25(OH)D3 levels were 18.78 ng/mL in total, 8.48 ng/mL in patients with vitamin D deficiency, and 19.69 ng/mL in patients without vitamin D deficiency. The prevalence of depression in CKD patients was higher compared to the general population (14.3% versus 11.1%, p=0.031). Moreover, the prevalence of depression was significantly higher in patients with vitamin D deficiency compared to those without vitamin D deficiency (27% versus 13.3%, p=0.022). EQ5D index of the group with vitamin D deficiency was lower than those without vitamin D deficiency (0.76 versus 0.85, p=0.024). Multiple logistic regression analysis showed that vitamin D deficiency was a significantly independent predictor of depression after adjusting for age, sex, hypertension, diabetes mellitus, anemia, smoking history, alcohol consumption, body mass index, proteinuria, and parathyroid hormone levels (odds ratio=5.135, 95% confidence interval=1.541 to 17.106, p=0.008). Conclusion: Depression was highly prevalent in CKD patients. The prevalence of depression was higher in CKD patients with vitamin D deficiency. In addition, vitamin D deficiency was a significantly independent predictor of depression in CKD patients. Therefore, determining vitamin D levels might be helpful in predicting depression in these patients.