本文把经济系统作为一类生灭过程来考虑 .应用人口控制论和森林系统的成功经验 ,研究经济系统的临界值问题 .首先 ,基于实际的经济分析、预测模型 ,在宏观层次上建立经济系统的控制模型 .连续模型便于理论研究 ,离散模型便于计算机仿真 .然后在这个控制模型的基础上 ,寻找使国民经济持续发展所需要的最小资产积累率表达形式 .本文得到的理论值将帮助我们更深刻地理解经济系统 In this paper, we consider the economic system as a kind of birth and death process.Using the successful experience of population control theory and forest system, we study the critical value problem of economic system.First, based on the actual economic analysis and forecasting model, we establish the economic system The continuous model is easy to be studied theoretically and the discrete model is easy to be used in computer simulation.On the basis of this control model, we look for the expression of the minimum asset accumulation rate needed to make the national economy sustainable development.The theoretical value obtained in this paper will help us to make more Understand the economic system