This study examined the potential of the mangrove ecosystem in Talengen Bay, North Sulawesi, Indonesia, for ecotourism development. Mangroves play a crucial role in environmental sustainability by supporting biodiversity, protecting coastlines, and providing habitat for aquatic species. The research aimed to assess the tourism suitability index and the regional carrying capacity of the mangrove areas, crucial for sustainable tourism planning. The study identified six mangrove species, with Rhizophora mucronata being the most dominant. The mangrove tourism suitability index (MTSI) was calculated based on parameters such as mangrove thickness, density, species diversity, tidal influence, and associated biota. The results indicate that the Talengen Bay mangrove ecosystem is suitable for ecotourism, with an average MTSI score placing it in the "Suitable" category. Additionally, the carrying capacity for mangrove tourism activities was determined to be 105 visitors per day, ensuring minimal impact on the ecosystem. These findings provide valuable insights for policymakers and stakeholders to promote ecotourism while ensuring the conservation and sustainability of the mangrove ecosystem in Talengen Bay.