【】 Objective To evaluate the relation of acute cerebral infarction to cerebral circulation time using contrast enhanced ultrasonography. Methods 37 patients with acute cerebral infarction were studied by contrast enhanced ultrasonograpy, then cerebral circulation time was calculated according to contrast time-intense curve. The differences of cerebral circulation time were compared between sides of cerebral infarction and non-infarction, the relation of cerebral circulation time to acute cerebral infarction was analysed, and predictive utility of cerebral circulation time for acute cerebral infarction was evaluated by ROC curve. Results Compared with sides of non-infarction, cerebral circulation time is longer in sides of cerebral infarction (6.151±1.817s VS 4.950±1.260s,t=3.305,P=0.0015). The cerebral circulation time is related to acute cerebral infarction (r=0.349,P=0.0023). The sensitivity and specificity to prediction of acute cerebral infarction by cerebral circulation time (cutoff value＞5.45s) was 59.46% and 78.38%, respectively and the area under ROC curve is 0.702(95% CI：0.584~0.802)(P=0.0010). Conclusion The cerebral circulation time by contrast enhanced ultrasonograpy is closely related to acute cerebral infarction.