The role of plasma adiponectin (ADPN) in patients with impaired kidney function and following kidney transplantation (Tx) is debated. We aimed to: (i) determine whether pretransplant ADPN level is an independent risk factor for deterioration of glucose tolerance including development of new-onset diabetes mellitus after Tx, (ii) describe which parameters that influence the ADPN concentration before and after Tx. Fifty-seven nondiabetic kidney allograft recipients and 40 nondiabetic uraemic patients were included. The Tx group was examined at baseline and 3 and 12 months after Tx. The uraemic control group was examined twice, separated by 12 months. ADPN levels declined significantly following Tx (P <0.0001), while estimated glomerular filtration rate (eGFR) increased (P <0.0005). eGFR, BMI and insulin sensitivity index were independently associated with ADPN in a multivariate regression analysis, whereas an ordinal logistic regression analysis revealed no predictive characteristic of ADPN for aggravation of the glucose tolerance after Tx. In conclusion, kidney transplantation is accompanied by a significant reduction in ADPN concentration. Several factors determine the ADPN concentration before and after Tx including kidney function, insulin resistance, use of immunosuppressive agents and BMI. Pretransplant ADPN level did not predict development of new-onset diabetes mellitus or even deterioration of the glucose tolerance following Tx.