This study examines the functions of collective action for people who experienced a disasters. Data were collected through ethnography and individual interviews with 22 people who participated in a silent walk, an anniversary event for the earthquake that occurred on February 6, 2023. The thematic analysis of the interviews and field reports identified the functions in three levels: First, at the individual level by contributing to people’s psychological well-being positively and giving people a sense of efficacy; second, at the community level by giving people a sense of shared identity with others; third, at the policy level by giving people a space to express their discontent with various political agendas. Additionally, the findings emphasize the necessity of policy-level change to ensure the sustainability of these transformations. The study contributes to the literature by highlighting that collective actions organized by people from public can be a significant step toward policy change.