Muslims must refrain from eating, drinking, smoking, and sexual relations from sunrise to sunset during the month of Ramadan, the ninth month of the Muslim calendar. Many Muslim kidney transplant recipients expressed their wishes to fast during Ramadan. Fasting during Ramadan is obligatory for every healthy, adult Muslim whereas the sick persons are among those exempt. The aim of our study was to evaluate whether repeated fasting in previous months of Ramadan adversely affects on kidney recipient volunteers. The study was carried out in the month of Ramadan (September to October 2007), average duration of fasting was 12 hours a day, volunteers were allowed to eat freely from Iftar to Sahar (sunset to dawn). All patients fasted during Ramadan in the study period and at least the previous two years. We observed 14 cases (13 male/1 female) with repeated fasting in previous Ramadan months (sum 97 fasting), their mean age 41.2 ± 9.9 years. We observed no significant change in serum creatinine and GFR from before to after Ramadan in our patients that fasted for equal or more 3 consecutive years (86.3 ± 29.1 and 88.2 ± 34.2 ml/min, P = NS), but most of other parameters were similar in both groups. Moreover, we found three recipients with good renal function who had fasted 12 consecutive Ramadan months. The current study indicates that there is no adverse effect associated with repeated fasting on allograft function.