Objective To study the effect of dexmedetomidine on renal function of donors of living-related renal transplants after nephrectomy.Methods Forty donors of living-related renal transplants were randomly divided into two groups: group A (n=20) and group B (n=20). 10-15 min before anesthesia induction, dexmedetomidine(1 μg/kg) was infused intravenously and 0.5 μg/(kg·h) was maintained 30 minutes before the end of the nephrectomy. An equal volume of normal saline instead of dexmedetomidin was given to group B. The concentrations of TNF-α, IL-6 and IL-10 were detected before anesthesia induction (T₁), immediately after nephrectomy (T₂), 24 hours(T₃) and 48 hours(T₄) after nephrectomy, respectively. Concentrations of serum urea nitrogen (BUN)[24 h, (6.41±1.23) mmol/L vs (9.24±1.25) mmol/L; 48 h, (6.62±1.30) mmol/L vs (8.41±2.4) mmol/L]and creatinine (Cr)[24 h, (98.2±4.7) μmol/L vs (111.4±5.1) μmol/L; 48 h, (104.4±6.2) μmol/L vs (119.5±8.2) μmol/L]were monitored before anesthesia induction, 24 and 48 hours after nephrectomy.Results Serum BUN and Cr in group A were significantly lower than those in group B at 24 and 48 hours after nephrectomy (P<0.05). The serum TNF- α and IL-6 concentrations in group A were significantly lower than those in group B at T₂-T₄,but the concentration of IL-10 was significantly increased (P<0.05).Conclusions Some dose of dexmedetomidine has protective effect on renal function after living-related renal transplants after nephrectomy in the early stage.