The duration of warm ischemia time is associated with short and long-term kidney transplant function. A quick rise in graft temperature is reported during the vascular anastomosis. This study was initiated, to gain insight into the effect of graft temperature on short-term transplant function. From 2013 to 2015, data of living donor kidney transplant recipients was prospectively collected. At set intraoperative timepoints, the graft temperature was measured using a non-contact infrared thermometer. Primary endpoint was measured glomerular filtration rate (mGFR) at 3- and 6-months post-transplantation. Univariable and multivariable associations were identified using linear regression analyses. Multivariable analysis included models with donor, recipient and procedure characteristics. We evaluated 152 patients, 83 (55%) were male, mean ±SD age was 50.3 ±13.4 years and 79 (52%) were pre-emptively transplanted. In univariable analysis graft temperature, after 10 minutes of warm ischemia, was significantly associated with 3- and 6-months mGFR, β -0.22 (95% CI -0.39 to -0.04, P=0.01) and β -0.22 (95% CI: -0.44 to -0.01, P=0.04). The association remained significant in multivariable models. An independent association between kidney graft temperature and 3- and 6-months mGFR was identified. This association opens up the opportunity to further investigate the clinical impact of kidney rewarming during transplantation.