Plant Syzygium Jambolanum is a well known Indian folklore medicine for treatment of diabetes mellitus. They have also reported to possesses anti-bacterial and anti-inflammatory activities .The in-vitro study was undertaken to investigate and confirm antidiabetic activity of the ethanol extract of the seeds using yeast model and to determine α- amylase inhibition. Percentage increase in glucose uptake by yeast was seen by varying; extract concentration and time. At high extract concentration yeast shows decrease in glucose uptake but shown increase in uptake at lower extract concentrations. It also showed very high percentage inhibition of α- amylase activity in a dose dependant manner when compared with a standard drug, Acarbose.