中文摘要：

关于区域经济发展的趋势，区域经济学界长期存在平衡发展与不平衡发展的争论。平衡发展与不平衡发展实际只是经济发展不同阶段的表象，它们将随时间的推移和经济的进步而周期性地演变与更替。介绍区域平衡发展与不平衡发展两种对立的理论，概述不平衡发展与平衡发展随时间演变的经验证据：“倒U假说”。在新古典经济学得出的增长轨迹基础上，利用简化的两地区逻辑曲线初步证明“倒U假说”的成立；并进一步讨论这一假说在多周期情形下的一个拓展，即地区差距的周期波动。

英文摘要：

This paper tries to demonstrate that balanced development and unbalanced development are just in nature superficial phenomena respectively in relation to different economic development phase,in which they would be displaced by each other. In the paper, the empirical evidence of the evolution of balanced development and unbalanced development is introduced, which is called inverse U hypothesis. Then the authors prove it by the logic curves of two regions on the basis of the track of economic growth which is concluded by a new classic economic growth model. In the end,it is further developed of the inverse U hypothesis from rnonocycle condition to multi - cycle condition with a new hypothesis, which is called cyclical fluctuation of regional disparity.