Aim of this study is to evaluate the in vivo and in vitro antidiabetic and antioxidant profile of standardized ethanol extracts of Bidens cernua L. var. radiata and B. frondosa L. Acute hypoglycemic activity of extracts were investigated on normoglycemic, glucose loaded and streptozotocin-induced diabetic rats. Sub-acute antidiabetic effect was investigated during the 8 days experiment. Both the extracts exhibited promising and significant hypoglycaemic effect in all tested in vivo models. Acute antidiabetic effect of B. cernua and B. frondosa were found as 40% and 42% at 500 mg/kg dose, respectively. -Glucosidase and -amylase inhibitory activity of the extracts were also determined and both of the extracts inhibited -glucosidase enzyme strongly (64.29-75.22% at 2 mg/mL). Conversely, in vitro antioxidant activity and total flavonoid content of extracts were measured. The extracts were standardized by RP-HPLC-DAD on the basis of cynaroside and chlorogenic acid as markers.