Abstract : α-Klotho is a co-receptor of fibroblast growth factor-23 (FGF-23) to carry out its biological function. αKlotho is produced mainly in the kidneys so that with decreased kidney function (decreased kidney mass), the production of α-Klotho decreases. Several other factors affect α-Klotho levels including age, BMI, DM, and hypertension. This study aims to determine the relationship between α-Klotho levels at various stages of Glomerulus Filtration Rate (GFR) in CKD. Observational research with a cross sectional approach at Wahidin Sudirohusodo Hospital and Unhas Hospital Makassar since April - Agustus 2021. Subjects is CKD patients which meet inclusion criteria. Intact serum FGF-23 levels were measured using an ELISA kit (Immutopics). Statistical analysis using Annova test, Mann Whitney and Spearman's correlation test, Statistical results are considered significant if p value < 0.05. This study included 77 subjects of CKD stage 3, 4, and 5 with a distribution of 39 men and 38 women. The results of the analysis found a decrease in-Klotho at each increase in CKD stage (p<0.05). The correlation shows that the lower the GFR levels, the lower the levels-Klotho (p<0.05). the level of α-Klotho is determined by the age factor (p<0.05). The decreasing of GFR is followed by decreasing of α-Klotho levels.