Tick-borne relapsing fever is an endemic disease in some parts of Iran. Borellia persica, the most common cause of this disease in Iran, has a wide geographic distribution and is present in Alborz and Zagros mountain chains.Here we report a 16–year-old male patient who presented with two episodes of fever within 15 days. He had a history of few overnight stays in a cave of mountainous area in Fars province. Sites of tick bites were found on exposed areas of extremities. Spirochetes were detected in Wright-stained smears of the patient's peripheral blood. He was successfully treated with penicillin. To the best of our knowledge, there has been no reported case of tick-borne relapsing fever from Fars province in the literature during the last 28 years.Tick-borne relapsing fever should be considered in patients with recurrent fever and peripheral blood smear should be investigated for spirochetes. Further seroepidemiologic studies should be carried out to determine the prevalence of this disease in Fars province.