The development of environment friendly bio-pesticides is now an area of intense research in the stored commodities. In the present research, we studied the feeding deterrent and contact toxicant properties of prenylated isoflavones derived from Derris scandens Benth against test larvae of red flour beetle, Tribolium castaneum Herbst and rice moth, Corcyra cephalonica S. Among all the compounds, Osajin (2), Lupalbigenin (4), Scandinone (5), Sphaerobioside (8) and Genistein (9) produced 100% contact toxicity to T. castaneum after

10th day and C. cephalonica after 15th day of treatment in food treatment assays. In the flour disc bioassay, compounds 2, 4, 5, 8 and 9 produced feeding deterrent activity against both the test larvae at the higher concentration tested. In the same assay, the relative growth rate (RGR), relative consumption rate (RCR) and food utilization (ECI) of test insects was significantly reduced with above test compounds even at lower concentrations. Compounds 2, 4, 5, 8 and 9 showed higher toxicity against both the larvae than other test

compounds at 10 µg /larva after 14th day of treatment in topical application method. Isolation of prenylated isoflavones from D.scandens may be important as a source of this material for stored pest control on wheat and jowar commodities.