The present study was carried out to evaluate the preliminary phytochemical screening and in vitro antidiabetic activity of Plumeria acuminata leaves. The leaves of Plumeria acuminata was extracted with different solvents and phytochemical investigations were done for all extracts using standard procedures. In vitro anti-diabetic activity of ethyl acetate extract of Plumeria acuminata (MEPA) was evaluated using α-amylase inhibition assay. The percentage inhibition increased in a dose dependent manner. In this study we investigated the better in vitro anti-diabetic potential of the Plumeria acuminata