BACKGROUND The incidence of ischemic stroke increases in winter. This study aimed to explore the effect of winter temperatures on the risk factors, etiology, coagulation, and degree of neurological impairment in patients with ischemic stroke using temperature and rainfall data from the Guangzhou Meteorological Bureau during the winter months of December, January, and February. MATERIAL AND METHODS We divided 112 patients with ischemic stroke into low-temperature and non-low-temperature groups. The low-temperature group experienced an average daily winter temperature of <13°C for five consecutive days within the 14 days before hospital admission and an average temperature of <13°C on admission. The non-low-temperature group experienced an average daily temperature of >13°C in the 14 days before hospital admission and an average daily temperature of >13°C on admission. Neurological deficits were scored and monitored using the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS) for disability in stroke. Blood pressure and coagulation indices of prothrombin time (PT) and thromboplastin time (TT) were recorded. RESULTS Compared with the non-low-temperature group, the low-temperature group showed a significantly increased proportion of patients with hypertension and large artery atherosclerotic stroke, more prolonged PT, and higher NIHSS scores. However, TT was reduced in the low-temperature group (P<0.05). CONCLUSIONS When the average winter temperature was <13°C, the risk factors, etiology, coagulation factors, and degree of neurological impairment of patients with ischemic stroke were significantly different from patients with ischemic stroke during warmer temperature.