Cognitive impairment is prevalent in patients with chronic kidney disease (CKD) and may be exacerbated by iron deficiency through impaired oxygen delivery and disrupted neuronal metabolism. However, no prior study has specifically examined the role of iron status in cognitive function among patients with non-dialysis CKD. This study aimed to investigate the associations of iron status markers (serum iron, transferrin saturation [TSAT], and ferritin) as well as hemoglobin with cognitive performance in CKD stages 3–5.