Collective memory about past events needs to be ‘recalled’ to influence current happenings. Social movements relying on collective memory to articulate and legitimize their identity and causes thus need to engage in memory mobilization, that is, organized efforts to bring collective memory to the fore for the purposes of social mobilization. This article examines and reconstructs the process of memory mobilization through the news media in the case of Tiananmen commemoration in Hong Kong. The analysis shows that social organizations attempted to make news through scheduling their actions in association with multiple temporalities and through engaging the established political institutions on the issue. The news media served as both messengers and mobilizers. Meanwhile, attempts to contest the movement’s representation of Tiananmen inadvertently contributed to memory mobilization due to the power of the dominant collective memory. The article illustrates how the dynamics of memory mobilization can impinge on commemoration of past events.