The majority of the people of Untung Jawa Island have the view that the mangrove ecosystem on the island has a very important impact and role for the lives of the people on the island. The impact and role of the mangrove ecosystem on Untung Jawa Island can be divided into physical functions, biological functions, chemical functions, economic functions, and tourism functions. However, the mangrove ecosystem on Untung Jawa Island is under increasing pressure due to both human activities and natural factors. Pressures and threats require all stakeholders to carry out various efforts to conserve mangroves on the coast of Untung Jawa Island. In order for mangrove conservation efforts on Untung Jawa Island to run effectively, it is necessary to measure public perceptions of the mangrove ecosystem. This study aims to investigate the perception of the people of Untung Jawa Island towards the preservation of the mangrove ecosystem. The results of the analysis show that the majority of the people of Untung Jawa Island have a positive and relatively high perception of the preservation of the mangrove ecosystem on the island. There are three factors that significantly influence the perception of the people of Untung Jawa Island on the preservation of the mangrove ecosystem; education level, place of origin, and type of work. This finding implies the importance of building a special system that can synergize economic interests and environmental interests in Untung Jawa Island.