To compare the choroidal thickness and ocular pulse amplitude (OPA) measurements obtained during the attack period in migraine patients and age and gender matched control group participants using high definition optical coherence tomography (OCT).Thirty eyes at the side of the headache of 30 subjects with a diagnosis of migraine with or without aura and unilateral migraine and 29 age and gender matched healthy participants were enrolled in this observational, cross-sectional study. OCT scans were performed to all participants. Choroidal thicknesses were measured at the fovea, 1500 μm nasal and 1500 μm temporal to the fovea. Intraocular pressure (IOP) and OPA were also measured.The choroidal thickness measurements obtained during the attack period in migraine patients were (mean±SD) 279.82±35.87, 250.05±29.49, and 239.58±27.92 and in control group were 308.20±44.97, 276.95±41.39, and 281.60±41.38 at foveal, nasal, and temporal measurement points, respectively. Choroidal thickness significantly decreased according to the control group (P0.05).Choroidal thickness was found to be significantly decreased in unilateral migraine patients during the attack period when compared with the control group, whereas OPA did not change. The possible implications of these findings on the association between migraine and glaucoma are discussed.