Abrus precatorius Linn. (Fabaceae), also known as "Saga Rambat", is commonly found in tropical countries, including Indonesia. The leaves of the plant are widely used commercially in Indonesia to treat cough and sprue. The aim of this research is to segregate and identify the chemical compound of A. precatorius leaf methanolic extract originated from Kebumen, Central Java, Indonesia. Dried leaves of A. precatorius were extracted with methanol then partitioned between n-hexane/water, methylene chloride/water, and ethyl acetate/water. The fractionation of the water layer was performed by various stationary phases. Identification of the chemical structure was performed by using data combination of 1D-NMR (1H-NMR and 13C-NMR), infra-red (IR), and mass spectrum (MS). Purification of water fraction from methanolic extract of A. precatorius leaves resulted in isolation of an alkaloid, identified as abrine or N-methyltryptophan. The isolated compound was also identified in five other origins of the plant in Java Island, Indonesia.