Objective To establish equations for predicting the 24-hour urine protein (24-UP)excretion by analyzing the correlation of four parameters including urine protein/creatinine ratio (Upro/Ucr), urine albumin/creatinine ratio (Ualb/Ucr), urine protein/osmolality ratio (Upro/Uosm) and albumin/osmolality ratio (Ualb/Uosm) with 24-UP. Methods Totally 530 patients were randomly divided into two groups, with 300 for establishing equations and the other 230 for testing the performance of the equations. The equations were set up by linear regression model. The performance of the equations was assessed by Pearson correlation, Bland-Altman plot, calculating the difference and ROC analysis. Results The equations were as follows: E1-UP (mg/24 h)=86.1 (Upro/Ucr \[mg/mmol\]) 0.595, E2-UP (mg/24 h)=53.5 (Ualb/Ucr \[mg/mmol\])0.704, E3-UP (mg/24 h)=21.3(Upro/Uosm \[mg/osm\])0.598, and E4-UP (mg/24 h)=10.9(Ualb/Uosm \[mg/osm\])0.698. Equation based on Ualb/Ucr achieved a better dependence and accuracy compared with the other 3 equations. However, ROC analysis showed no significant difference in diagnostic performance among the 4 equations. We also noticed that excellent correlation was found between the predicted urine protein excretion and 24-hour protein excretion when the patients were at CKD 1 to 4 stages. When patients were at CKD 5 stage, the accuracy and dependence of the equations fell sharply. Conclusion Though the correlation and accuracy of Ualb/Ucr are better than the other 3 Methods , the overall performance is not significantly different among the 4 Methods .