Cockroft-Gault (CG) and abbreviated Modification of Diet in Renal Disease (MDRD) equations allow FOR an indirect estimation of glomerular filtration rate (GFR) in patients with chronic kidney disease (CKD). The aim of this study was to correlate the estimate of the GFR by creatinine clearance (Cr Cl) in 24-hour urine and the equations of CG and abbreviated MDRD. One hundred and six (106) patients diagnosed with non terminal CKD were included, (64 women and 42 men), with a meanage of 65 ± 15.7 years. Hypertension and type 2 diabetes mellitus were the major morbidities associated to CKD. The Spearman coefficient was used for the association between 24 hours Cr Cl in urine with the CG and abbreviated MDRD equations and by sex and age group. The equation of CG showed a greater correlation to estimate than the TFG abbreviated MDRD equation, as well as women and older than 65 years, with correlation coefficients of 0.763 (p value= 0.000), 0.813 (p value=0.000) and 0.761 (p value=0.000) respectively. In conclusion, in patients with CKD that is not terminal, the equation of CG has better correlation with GFR estimated by Cr Cl in urine 24 hours than the abbreviated MDRD equation.