Citywalk, as a cultural and tourism activity that has regained popularity on internet social platforms, possesses distinct communication characteristics. By combining case analysis with the theory of Participatory Culture, a Citywalk service system design method, “From Participation to Convergence” is proposed. This method covers three levels: Service Elements, Cultural Dissemination, Experience Effects, and five dimensions: Multi-media, Community Building, Personalized Interaction, Scene Narrative, Service Dissemination, as well as its influencing mechanisms. From a communication perspective, the Citywalk Service System Design Method can not only empower Citywalk users and enhance their satisfaction, but also deepen and broaden the depth and breadth of urban cultural tourism services.