To evaluate the regulating effect of Buyang Huanwu decoction and its simple prescription (Naojian tablet) on CDK4/Cyclin D1 expression in hippocampus tissues of rats with cerebral ischemia, SD rats were divided into the sham-operation group, the model group, the Buyang Huanwu decoction group (ig, 3.15 g · kg⁻¹) and the simple prescription group (ig, 2.41 g · kg⁻¹). Each group was further divided into five subgroups based on time points after the administration, i. e. 1 d, 3 d, 7 d, 14 d and 28 d, respectively. CDK4/Cyclin D1 expressions of the group at different time points were examined by using immunohistochemistry and real-time qPCR. According to the results, the cerebral ischemia model group showed higher CDK4/Cyclin D1 expression than the sham-operation groups (P < 0.05), suggesting that the cell cycle signal pathway would be activated by the cerebral ischemic injury. Both Buyang Huanwu decoction and simple prescription groups showed significantly lower cyclin expression than the model group at 3 d, 7 d, 14 d, 28 d (P < 0.05), indicating both Buyang Huanwu decoction and its simple prescription could play the neuroprotective effect through the cell cycle signal pathway.