Mice pathological model of acute cerebral ischemia was established. In order to observe the effect of salvianolic acid B (Sal B) on brain energy metabolism and hydrocephalus in the brain of mice at different ischemic times, the energy charge (EC), content of phosphocreatine (PCr), level of lactic acid (Lac), activity of Na+ -K+ -ATPase, brain index and water content of brain were measured at 6, 12, 18, 24, and 30 min, separately after ligating bilateral common carotid arteries in mice. NIH mice were randomly divided into sham-operated group (sham), cerebral ischemia group (ischemia), Sal B-treated group (Sal B) and nimodipine-collated group (Nim). At 6 min after cerebral ischemia, EC, content of PCr and activity of Na +-K -ATPase began to decrease, while level of Lac, brain index and water content of brain increased gradually. However, Sal B (22.5 mg x kg(-1) improved pathophysiological changes at different ischemic times. Especially at 30 min after cerebral ischemia in Sal B group, EC (P < 0.01), content of PCr (P < 0.01 and activity of Na+ -K+ -ATPase ( < 0.05) increased significantly. Meanwhile, level of Lac (P < 0.01, brain index (P < 0.01) and water content of brain (P < 0.05) were lower obviously than those of cerebral ischemia group. Sal B could alleviate hydrocephalus by the improvement of energy metabolism in mice with acute cerebral ischemia, that provides scientific evidence that Sal B can be used for the clinical application of ischemic diseases.