Recent studies have shown that mental state is affected by seasonal changes. This is called as seasonality. In the present study, it was aimed to determine the proportion of seasonality on totally 160 medical students (92 males, 68 females) from Fırat University Medical Faculty. Subjects were used in Seasonal Pattern Assessment Questionnaire. Sixty four students (40%) reported that seasonal changes were problem for themselves. In our study, the mean Global Seasonal Score (GSS) was 12.24±7.32. Males had a significantly higher GSS than females (13.42±4.73 in males, 10.80±2.62 in females). Subject reported that they felt better feeling in summer (57.3%) and in spring (27.8%). Also, they reported more social activities in summer (54.9%) and in spring (24.1%) and lowest amount of sleep in the summer (10.6%). We found that students in our region were affected by seasonal changes.