Fruit and leaves of junipers are commonly used internally as tea and pounded fruits are eaten to lower blood glucose levels in Anatolia. Thus, we aimed to evaluate antidiabetic and antioxidant potential and the chemical profile of Juniperus foetidissima Willd. and J. sabina L. in this study. In-vitro antidiabetic activities of leaf and fruit extracts were examined by their inhibitory activity on a-glucosidase and a-amylase enzymes. Then, in-vivo antidiabetic activities of leaf and fruit extracts of Juniperus species were investigated on streptozotocininduced diabetic rats. Additionally, antioxidant activities (phosphomolybdenum, ferric-reducing antioxidant power and ABTS radical scavenging activity assays), phytochemical screening tests and high performance liquid chromatography analysis (HPLC) were done. In-vitro enzyme inhibitory effects of the extracts were supported by the results of in-vivo antidiabetic activity studies. Phytochemical screening tests indicated presence of flavonoids, tannins, terpenoids and carbohydrates in the extracts. Amentoflavone was identified as the major compound in the extracts and content of amentoflavone was determined. As a result, Juniperus extracts and its active constituents might be beneficial for diabetes and its complications.