The paper, based on the concept and the elements of human resource ecosystem (HR Ecosystem), studies the function and structure of HR Ecosystem, introduces the entropy theory to define the content of entropy of HR Ecosystem, constructs the corresponding distinctive model to distinguish the direction of the evolution of HR Ecosystem and the evolutionary entropy model, and applies the models to demonstrate the evolutionary rules of HR Ecosystem. The study shows that the entropy theory can be well applied to the analysis on HR Ecosystem and that it opens up a new field in the research of human resource management and provides a new effective technical method. The paper, based on the concept and the elements of human resource ecosystem (HR Ecosystem), studies the function and structure of HR Ecosystem, introduces the entropy theory to define the content of entropy of HR Ecosystem, constructs the corresponding distinctive model to distinguish the direction of the evolution of HR Ecosystem and the evolutionary entropy model, and applies the models to demonstrate the evolutionary rules of HR Ecosystem. The study shows that the entropy theory can well apply to the analysis on HR Ecosystem and that it opens opens a new field in the research of human resource management and provide a new effective technical method.