Objective To investigate the diagnosis and differential value of multi-slice spiral CT in hyperacute (0-6h) massive cerebral infarction. Methods A total of 420 cases of patients who were highly suspected with massive cerebral infarction in our hospital during the past year (February 2017 to February 2018) were given head CT plain scan at the onset of 0-6 h, and were given head CT review or other clinical related examinations later (12-24 h and 24-72h of after onset). The CT examination results and the final clinical diagnosis results were compared, and the diagnostic value of MSCT in the diagnosis of hyperacute massive cerebral infarction (0-6h of onset) were analyzed. Results Within 0 to 6 hours of onset, there were 208 cases of massive cerebral infarction positive patients and 212 cases of massive cerebral infarction negative patients (such as cerebral hemorrhage, lacunar infarction, etc.) by MSCT, and 359 cases were eventually diagnosed as massive cerebral infarction by clinical diagnosis. The sensitivity, accuracy and specificity of MSCT in the diagnosis of hyperacute cerebral infarction were 57.9%, 100.0% and 64.0% respectively. With the prolongation of onset time, the detection rate of MSCT examination in massive cerebral infarction was significantly increased, and all cerebral infarctions were basically detected after 24h of onset. Conclusion Although the sensitivity of CT in the diagnosis of acute cerebral infarcion needs to be improved, the specificity is high and the operation is convenient. It can win precious time for the patients with acute severe cerebral infarction and can be used to diagnose early cerebral infarction.