Objective To observe the effects of Bushen Yizhi Decociton (BYD) on somatostatin-like (SS-like)neurons in hippocampal gyrus of rat models with Alzheimer's disease(AD). Methods Fifteen-month_old AD rat models were established by intraperitoneral injection of D-galactose for 4 weeks combined with ibotenic acid injection into bilateral nucleus basalis of Meynert. AD model rats were randomly allocated to AD model group(Group C), Hup-A treatment group(Group D) and BYD treatment groups (Group E and Group F,treated with high dosage and low dosage respectively), and 10 normal aged rats (Group B)and 10 normal youth rats (Group A)served as the normal control groups. The methods of immunohistochemistry and dig_labeling c-DNA probe in situ hibridization were used to detect the number of SS-like immunoreactive positive and SS mRNA expressed positive neurons in hippocampal CA1 and CA3 fields and the dentate gyrus. Results The number and optic density of SS-like immunoreactive positive and SS mRNA expressed positive neurons were higher in BYD treatment groups than those in Group C (P< 0.05 ?or? 0.01 ).The differences of the above indexes among some groups were significant (P< 0.05 ?or? 0.01 ). Conclusion BYD possesses a certain protective effect on SS-like neurons in hippocampal gyrus of rat models with AD.