Abstract： Objective To investigate the effect of cyclosporine blood level at first year after kidney transplantation on patients with a survival time over 10 years. Methods 380 patients with functional allograft, a survival time over 10 years and long-term administration of cyclosporine A (CsA) were studied, and received CsA-based treatments. According to the blood CsA level at the first year after kidney transplantation, patients were divided into five groups: group 1, blood CsA level was above 0. 208 μmol/L (1 μmol/L = 1201.9 μg/L), group 2, blood CsA level between 0. 166-0. 208μmol/L; group 3, blood CsA blood level between 0. 125-0. 166 μmol/L; group 4, blood CsA blood level between 0. 083-0. 125 μmol/L; group 5, blood CsA level less than 0. 083 μmol/L. Systolic blood pressure (SBP), diastolic blood pressure (DBP), serum creatinine(SCr), uric acid (UA), cholesterol (CH), triglyceride (TG), alanine aminotransferase (ALT), direct bilirubin (DBil) and total bilibubin (TBil), albumin (Alb), hemoglobin (Hb), count of white blood cells and positive rate of proteinuria in 5 groups at the 1st, 5th and 10th year after kidney transplantation were analyzed. Results At the 5th year SBP in groups 1 and 2 was higher than in groups 3, 4 and 5. UA level in group 5 was lower than other groups, and Alb level in group 5 was higher than other 4 groups. Proteinuria positive rate in groups 4 and group was lower than other groups. At the 10th year after kidney transplantation,indexes among 5 groups had no statistically significant difference, except for SBP, DBP, DBil and CH in some groups. There was also no significant difference in SCr level among 5 groups at the 5th or 10th year after transplantation. Conclusion Blood CsA levels at the first year after kidney transplantation has no significant effect on long-term allograft function. But higher level of CsA (＞0. 166μmol/L) at the first year maybe predict high rate of hypertension, high blood UA and proteinuria at the 5th and 10th year after transplantation.