The extraction process was studied by taking the concentration of ethanol,extraction time,times of extraction,solid-liquid ratio and particle size as test factors and extraction rate(productivity) as test target.The test was performed by uniform design method and the model was established by Artificial Neural Networks(ANN).The paper studied systematically the time characteristic in extraction process based on the trained neural networks model by our neighboring analysis of multifactor and multilevel.Through the model instruction,a number of verifying tests were done and the results were well consistent with the model calculation.A set of optimized process parameters was obtained: the concentration of ethanol is 65%,extraction time 15min,times of extraction 2,solid-liquid ratio 10,and particle size 40 meshes.The yield is 91.40%(value of model calculation is 91.38%).The conclusion is that the influence of extraction time on the yield of ursolic acid extraction is nonlinear and this influence is varied with other extracting conditions.