The continued growing model for national economy has been discussed. On the bassis of the continued growing model, the speed change control growing model for national economy has been presented. It has been found that the periodic change and period dubling of the gross national product have taken place under the regulation of growing rate when the growing rate leads to a certain value, chaos behavior in the gross national product will appear. Qualitative change of the gross national product has been shown very complicated dgnamcics features.