Sister city cooperation has emphasised the role of the state and local government However, the role of the community is also essential.although has been relegated to a second place. This article aims to apply the model of community involvement in the sister city’s flood prevention cooperation plan in Samarinda city, East of Kalimantan, emphasizing the active citizen participation (citizen diplomacy). The analysis of community involvement with the bottom-up model in sister city cooperation starts with the identification of flooding problems in three samples of Saramarinda urban villages presenting its performance and outcomes. This approach is new in solving the Samarinda flood problem, which so far has tended to be centralized and ineffective.