Background: Several case series of patients with Tolosa-Hunt syndrome have been described in the literature; however, few studies have focused on the cerebrospinal fluid (CSF) characteristics. This study aimed to analyse the CSF characteristics of patients with Tolosa-Hunt syndrome. Methods: Fifty-five patients who fulfilled the 3rd Edition of the International Classification of Headache Disorders diagnostic criteria for Tolosa-Hunt syndrome were included in this study. We retrospectively analysed data on CSF parameters, imaging findings, and clinical characteristics of these patients. Results: Oligoclonal bands (OBs) were detected in the CSF of 13 (13/44, 29.5%) patients. The sex ratio was balanced. The mean age at onset of Tolosa-Hunt syndrome was 46.9 +/- 10.23 (range 22-72) years. Eight (8/13, 61.5%) patients had multiple cranial nerve palsies. Lesions limited to the cavernous sinus were found on magnetic resonance imaging in 7 (7/13, 53.8%) patients. OBs were significantly detected more frequently in patients whose samples were evaluated less than 30 days after the onset of this diseases (p = 0.026); however, there were no significant differences in the protein level (p = 0.360) and IgG synthesis rate (p = 0.614). Conclusions: The detection of OBs in the CSF of patients with Tolosa-Hunt syndrome was not rare. It would be interesting to follow-up patients with OBs to determine whether they eventually developed an otherwise more specific inflammatory diagnosis.