Abstract: As a type of coastal vegetation, mangroves are valuable, unique, and vulnerable. Mangrove ecosystems have a distinctive vegetation structure, which consists of several characteristics sequentially, such as trees, saplings, poles, and seedlings. This study aims to assess and monitor the structure and composition of mangrove vegetation in Makassar City, South Sulawesi. Field surveys were conducted to measure and monitor mangroves in two different areas, namely coastal areas and small islands. The highest mangrove density is at Station 2, which is 0.59 ind/m2, which is a river area. The station with the lowest density is at Station 1, which has a value of 0.23 ind/m2, which is a coastal area. Avicennia marina, Rhizophora apiculata and Acanthus ilicifolius were found to have the highest importance value index. Location 1 is the least stable because it only has the Avicennia marina mangrove species. Meanwhile, at location 3 (Lakkang Island, a small island), there are variations in the value of each index, although it is still in the low category. This means that in general, each research location has a less stable ecosystem. Furthermore, this study can contribute to conservation, biodiversity assessment, and sustainable mangrove ecosystem management strategies.