Platform economy is a new economic form formed by the development of Internet platforms to a relatively advanced stage. Currently, the platform economy in China presents a situation of coexistence of monopoly and competition on the whole, and a highly concentrated market structure in the relevant segments. However, specific analysis needs to be done when it comes to monopoly behaviors. The platform economy has the characteristics different from the traditional economy, such as network effect and cross-border nature. The anti-monopoly theory and practice need to make timely response and necessary reform. In the field of platform economy, China's anti-monopoly should pay attention to the balance between competition and innovation, and give detailed rule guidance. Although hot issues such as “Select One in Two” and “use big-data analysis to price products to the disadvantage of existing customers” on Internet platform may constitute monopolistic behavior, they need to be brought into the corresponding institutional framework of anti-monopoly law for rigorous competition analysis and legal demonstration.