The efficiency of eight plant oils was tested against Sitophilus oryzae L.    adults using the treated wheat grains technique. The oils were rue, frankincense, juniper, shallot, fenugreek, cabbage, and nactom and marjoram. The high doses caused high mortality (67.8- 97.8%) after 3 days of exposure and a complete  mortality (100%) after 7 days. While this effect continued up to five months for some oils as marjoram and cabbage, it lasted two months only with nactom, frankincense and juniper and one month with other oils. The LC50 level of all oils reduced       greatly the number of eggs with about (94- 100%) and no offspring was obtained. Treatment of wheat grains with the tested oils had had in some cases a clear   adverse effect on the grain germination. This effect, on water absorption was slight with no clear trend comparing with the control.