Abstract: The rapid development of platform economy based on digital technology has formed competition and integration with the capital cycle dominated by financial capital.The core of digital platforms is traffic, while the core of financial activities is credit and expectations.The expansion and financialization of digital platforms driven by capital are based on flow, credit, and expectations.The credit mechanism in financialization promotes the realization of traffic, enhances valuation expectations through platform leverage, and realizes overvalues through credit expansion, further attracting users' attention and expanding traffic, forming a spiral of “traffic-credit-expectation”.The competitive convergence of platform expansion and financialization takes various forms:First, through monetization and capitalization, financialization realizes the valuation and realization of digital platform traffic;Second, with the help of internal flow micro-cycles, digital platforms extend credit to the entire social network and improve financialization;Finally, there is a full range of competition between digital platform expansion and its financialization regarding traffic, credit, and expectations.

Key words: digital platform expansion, financialization, flow micro-cycles, credit realization, users' attention