Cognitive dysfunction including dementia is a common complication of chronic kidney disease (CKD) that has just been recently appreciated. It has negative outcomes in the management of patients with CKD. This study explored the possible biochemical and clinical features of patients with CKD that can predict the occurrence of cognitive impairment in patients with moderate to severe CKD. We evaluate patients with stages 3-5 CKD for the occurrence and predictors of cognitive impairment. Multiple areas of cognitive function were tested in this single-center study using Community Screening Interview for Dementia (CSID) and Trial-Making Test A (TMTA)/Trial-Making Test B (TMTB). Cognitive impairment was correlated with patients’ routine biochemical, hematological, and selected clinical parameters. We observed a negative correlation between cognitive impairment and patient’s serum calcium (r 5 0.240; p 5 0.033) and estimated Glomerular filtration rate (eGFR) (r 5 0.379; p 5 0.0006). Therefore, eGFR is an accurate predictor of cognitive dysfunction in patients with moderate to severe CKD. Early evaluation of cognitive function in CKD is indeed advised for optimal outcome in the management of patients with CKD.