The present study was performed to investigate the local ethno medical claim scientifically by screening the acute hypoglycaemic effect of Delonix regia seeds in normal and streptozotocin induced diabetic mice. It has also significantly improved the glucose tolerance in normal mice. The study comprises the evaluation of antidiabetic activities of Delonix regia belonging to Leguminosae family. Initially, In vitro α-amylase inhibitor activity was performed as a preliminary screening for petroleum ether, ethyl acetate, ethanol and aqueous extracts of the plant. In comparison with all the extracts, ethanol extracts shown promising activity with IC₅₀ values of 550.29μg/ml for D. regia respectively. Hence EEDR were further selected for DPPH radical scavenging activity. Delonix regia resulted in 455μg/ml in DPPH radical scavenging activity. Hence, EEDR was selected to evaluate In vivo Antidiabetic activity.