Sago (Metroxylon spp.) is an important crop in Maluku. This study aims to identify the biodiversity of sago palm and understorey vegetation around sago clumps in Maluku. The research was carried out in six sago area from September 2015 to October 2016. The Sago Plant identification was carried out through the growth phase of sago, i.e. seedlings, saplings, weaning, trunks, and ripening. Vegetation observation was done in radius 100 m2 surrounding sago clumps. The result shows that Metroxylon rumphii Mart type. (Tuni sago), M. sagus Rottb. (Molat sago) and M. Silvester Mart. (Ihur Sago) dominates sago palms area in Seram and Ambon Islands, Maluku. There are significant morphological differences between the types of sago, especially in stem height, midrib width, leaf midrib colour, number of thorns, and flower stalk length, as well as the difference of carbohydrate content. Understorey vegetation of each observation sites diverse consist of 15 families and 20 species. The families that dominate the vegetation under the sago palms are Araceae, Thelypteridaceae, and Athyriaceae. The types of plants from Araceae are taro types and broadleaf, while those from the Thelypteridaceae and Athyriaceae families are types of ferns.