This study was performed to demonstrate alpha-glucosidase and alpha-amylase enzyme inhibitor activities using the methanolic extracts of Elaeagnus angustifolia leaves. Methanolic extracts were prepared by two different extraction methods [accelerated solvent extractor (ASE) and Soxhlet apparatus]. The analytical procedure involved the application of liquid chromatography. Our results showed that the ASE extracts inhibited a-amylase (10-100 mu g/ml) and alpha-glucosidase (10-50 mu g/ml) dose-dependently exhibitedrp inhibitory activities with the extracts [alpha-amylase (40%) and alpha-glucosidase (56%)]. RP-HPLC analyses of the methanolic extracts were detected with vanillic acid and 4-hydroxybenzoic acid as the main phenolic acids in all the ASE extracts. Elaeagnus angustifolia leaf extracts may be attributed to the presence of vanillic acid and 4-hydroxybenzoic acid, there by confirming with its traditional use for the management of diabetes mellitus. We implicate that the anti-diabetic activity through in vitro assessments and support to the folkloric use of this plant for controlling type-2 diabetes mellitus in Turkey.