Abstract: The market structure of China's coal industry has the characteristics of gradually increasing industrial concentration, differences in enterprise size, weak product differentiation, and high barriers to entry and exit the industry. It cannot be simply classified as a single type of market structure in Economics. Its long-term contract trading and short-term contract trading are characterized by oligopoly and monopoly competition, respectively. Market structure is closely related to corporate behavior. In the process of transformation and upgrading to achieve high-quality development, coal enterprises should determine their appropriate competition strategies,based on the realization of the different characteristics represented by long-term contract trading and short-term contract trading ,and also of their market positions in the industry.