Mangrove is an ecosystem that is a habitat for various both aquatic and terrestrial biota. This research aims at revealing the distribution and community structure of mangrove in Donrotu, Guratu and Manomadehe Islands, West Halmahera Regency, North Maluku. This work was conducted from April to June 2019. Data collection using the spot check method, while the analysis of mangrove distribution was carried out qualitatively. Community structures quantitatively include type density (Di), relative density types (RDi), frequency types (Fi), relative frequency types (Rfi), closing types (Ci), closure of relatively types (RCi), and Important value (VIi). The results showed that Rhizophora stylosa in the three islands (Donrotu, Guratu, and Idamdehe) had the highest species density and highest density values. Closing types and closures are relatively varied. The type of R. stylosa also has a higher importance in all three islands. The highest mangrove density was mainly found in Donrotu Island (0.96 ind/m2), then Guratu Island (0.46 ind/m2), and Idamadehe Island (0.32 ind/m2), respectively.