Abstract: AIM: To observe the effect of the Yizhifang and its analytic prescription on learning and memory in the ovariectomized mice. METHODS: Five pieces of different analytic prescriptions were composed of three groups of herbal medicines, applying the uniform design of experiments with mixtures (UDM).The mice were fed with these prescriptions and then the ability of learning and memory of these mice were measured in the test of special searching and location. RESULTS: One optimal prescription, mainly consisted of the medicine tonifying the kidney, can improve the ability of special learning and memory in ovariectomized mice. CONCLUSION: It is feasible and convenient to analyze the prescription of a larger formula with UDM.

Key words: uniform design of experiments with mixtures, learning andmemory, Yizhifang, analytic prescription, medicine tonifying the kidney, Morris water maze