BACKGROUND The aim of this study was to analyze the changing role of thrombelastography (TEG) by detecting the indexes of TEG in patients with acute cerebral hemorrhage and cerebral infarction, combined with pathogenesis, and to find objective laboratory indexes for the diagnosis and treatment of cerebrovascular diseases. MATERIAL AND METHODS Data from 150 patients were collected, including 69 cases identified as the cerebral infarction group and 81 cases identified as the cerebral hemorrhage group. In addition, 50 healthy adults were selected as a control group. The cerebral hemorrhage group was divided into 3 subgroups according to the amount of bleeding: small hemorrhage group, moderate hemorrhage group, and large hemorrhage group. The diagnosis for each participant was mainly based on computed tomography (CT) and magnetic resonance imaging (MRI). TEG indexes [R value (coagulation reaction time), K value (coagulation time), Angle (reflecting the formation rate of blood clot and the function of fibrinogen), MA (maximum thrombus amplitude), CI (coagulation index)] were measured by TEG YZ5000 instrument. RESULTS The cerebral infarction group had lower R and K values and higher Angle and CI (P<0.05). The cerebral hemorrhage group had higher K value; the Angle and MA were lower in the moderate hemorrhage group and in the large hemorrhage groups (P<0.05). In the cerebral hemorrhage group, Angle and MA were negatively correlated with the amount of cerebral hemorrhage (r=-0.475, -0.394 respectively, P<0.05), and the K value was positively correlated with the amount of cerebral hemorrhage (r=0.337, P<0.05), while the R value had no significant correlation with the amount of cerebral hemorrhage (r=0.251, P>0.05). R and K values in the cerebral infarction group were significantly lower, while Angle, MA, and CI were significantly higher in the cerebral hemorrhage group. CONCLUSIONS K value, Angle, and MA may be of value in the assessment of the amount of cerebral hemorrhage.