While searching for ${alpha}$-glucosidase inhibitors, the active compound was found in a methanol extract of Burthus martensi Kirsch. The separation of the active compound was performed using various chromatography methods and the physico-chemical properties of the purified compound were characterized. The compound showed very potent inhibitory activity against ${alpha}-glucosidase$ with an $IC_{50}$ value of $5.3;{mu}g/ml$. Lineweaver-Burk plot indicated that its inhibition of ${alpha}-glucosidase$ was competitive.