Abstract: OBJECTIVE To study whether orally administrated sodium bicarbonate slows the decline of renal function in chronic kidney disease (CKD). METHODS All of 110 patients with CKD were randomly divided into sodium bicarbonate group and placebo group, and received the treatment with sodium bicarbonate or placebo for 2 years. Decline rate of glomerular filtration rate (eGFR), the ratio of patients with rapid decline of eGFR>3 mL·min^-1·(1.73 m)^-2·y^-1 developed to end stag renal disease(ESRD) eGFR<10 mL·min^-1·(1.73 m)^-2 were estimated before and after the treatment. Serum albumin and dielary protein intake were measured at the same time. RESULTS Compared with placebo group, decline in eGFR was slower in sodium bicarbonate group(P<0.05) after treatment of 2 years. Patients in bicarbonate group were significantly less than experience rapid progression(P<0.05). Fewer patients in bicarbonate group developed ESRD(P<0.05). Nutritional parameters improved significantly in bicarbonate group. CONCLUSION Bicarbonate slows the rate of progression of CKD to ESRD and it improves nutrition status among patients with CKD.