Leptin is secreted mainly by fat, which is involved in energy metabolism and reproduction. Leptin and its receptor (Ob-R) have been detected in human spermatozoa and testis, thus it can be concluded leptin involves in male physiology. The goal of this study was determination of the presence of leptin receptor mRNA in the ram testis, epididymis and spermatozoa by reverse transcription polymerase chain reaction (RT-PCR).Ejaculated spermatozoa from ten fertile Taleshi ram were collected by means of an artificial vagina. Testes, placental cotyledons and adrenal glands were obtained from abattoir. Placental cotyledons and adrenal glands were used as the positive control. Epididymal spermatozoa recovery was performed from epididymis. To purify spermatozoa, motile sperm were isolated by the swim-up procedure. Total RNA was isolated from epididymal spermatozoa, ejaculated spermatozoa, adrenal gland and placental cotyledon and then they were purified. The mRNA for the long form (Ob-Rb) and the short form (Ob-Ra) of leptin receptor was detected in testis. RT-PCR analysis of total RNA from epididymal spermatozoa and ejaculated spermatozoa revealed the presence of leptin mRNA in these cells. The mRNA for Ob-Rb was observed in epididymis and epididymal spermatozoa, but the Ob-Ra mRNA was absent. The presence of Ob-Ra mRNA was found in ejaculated spermatozoa, whereas Ob-Rb mRNA did not exist. It can be concluded that the mRNA for leptin receptor is present in ram gonads and spermatozoa.