State-owned enterprises are an important material and political foundation of socialism with Chinese characteristics, and have always held a prominent political and economic position in China’s economic system reform. Since the Third Plenary Session of the Eleventh Central Committee of the CPC in 1978, which initiated the reform of granting more autonomy and profit-sharing in state-owned enterprises, the pace of state-owned enterprise reform has never stopped; instead, it has advanced step by step and continuously deepened. The reform of state-owned enterprises in each period is constrained by the development requirements and reform conditions of that period, and requires wisdom and courage. As the main content of economic system reform, the reform of state-owned enterprises is the most difficult and crucial, and it determines the direction of China’s development, directly related to the balance among reform, development, and stability. Since the 18th National Congress of the CPC, facing the new situation and new tasks of the transformation of socialist contradictions and the shift from high-speec to high-quality economic development, state-owned enterprises have undergone fundamental changes in party building leadership, strategic security, supervision and assessment, active flexibility, proactive innovation, and technological leadership through comprehensive deepening reforms. They have continuously strengthened, optimized themselves, enhancing their core functions and competitive edge. This highlights the leading position of state-owned enterprises in the construction of Chinese path to modernization, and reflects the superiority of the socialist system. The 46-year reform of state-owned enterprises has gone through a difficult but successful path, proving both theoretically and practically that public ownership can be well integrated with the market economy, greatly enriching and developing Marxist political economics and scientific socialist theory.