Purpose: Tacrolimus, an immunosuppressive agent, is used especially after organ transplantation. It has been asserted that tacrolimus has protective effects on the auditory system in some studies while it has negative effects in other studies. The purpose of our study is to investigate the effect of tacrolimus on the inner ear of the rats. 
 Materials and Methods: 20 healthy Sprague Downey male rats weighing 250-350 grams were included in our study. The first group of rats were given 1mg/kg tacrolimus (n:7), the second group of rats were given 0.1 mg/kg tacrolimus (n:7), and the third group (n:6) was the non-administered control group. The first measurements of all rats were taken with distortion-product otoacoustic emission before starting the experiment. Then, tacrolimus drug was administered by gavage method to the 1st and 2nd groups along 30 days. The last measurement was repeated on the 30th day.
 Results: According to the results of the first measurements, emission was obtained in all rats and the responses were found to have similar characteristics. Similarly, the difference between the signal noise rate values in the last measurements taken from the groups did not show any statistical significance.
 Conclusions: Based on the distortion-product otoacoustic emission measurements, it can be said that Tacrolimus does not have ototoxic effects on the auditory system of rats considering the administered dosage and time.