The Influence of aqueous extract of Eucalyptus was examined during 2018. By applying the water extract of eucalyptus to different weed species, namely Bindweed, barley, London rocket, wild safflower, Wild oat, common lambsquaters, Bird’s seed grass, Broad leaved dock and Umbrella milkweed .In addition to the control, 10 ml of dry leaf water extract was applied at intervals of 3 days for each treatment. The data obtained after 20 days showed that the fresh weight and dry weight of each tested weed were significantly reduced compared to the treatment with water (control). Germination, root length (cm), shoot length (cm) and chlorophyll content of the weeds are adversely affected by the application of the extract instead of the control. These results indicate that the water extract of eucalyptus can be used as a biological inhibitor of weed control in our planting systems.