通过构建市场分割条件下的混合所有制经济竞争模型,本文对全国性国有企业在中国改革发展过程中的作用提供了新的解释。全国性国有企业在参与区域竞争的过程中,具备一种区域整合的功能:它面向全体市场的决策与分别面向各区域市场的决策等价,全社会总剩余最大化目标也可以分解为各区域社会剩余最大化的子目标之和,在其效率较高的情况下,将迫使地方企业改进成本或者退出市场,而只有当地方企业有足够高的效率的时候,全国性国有企业才会选择退出策略。国有企业事实上可以作为一种内部规制工具对市场分割的负面效应进行一定程度的制衡,在明确规制规则的条件下,我们可以通过动态调整企业目标函数以实现整体市场福利的最大化。 By constructing a mixed-ownership economic competition model under the condition of market segmentation, this article provides a new explanation for the role of the national state-owned enterprises in the process of China’s reform and development. In their participation in regional competition, the national state-owned enterprises have the function of regional integration: their decision-making for the entire market is equivalent to that for each regional market, and the goal of maximizing the total social surplus can be decomposed into various regions The sum of the sub-goals of maximizing social surplus will force local enterprises to improve their costs or exit the market if their efficiency is high. Only when the local enterprises have enough efficiency, will the state-owned enterprises opt out Strategy. In fact, state-owned enterprises can be used as an internal regulatory tool to check and balance the negative effects of market segmentation to a certain extent. With the explicit regulation of rules, we can maximize the overall market welfare by dynamically adjusting the objective function of the enterprise.