Seed identification of some forgein seeds, which were recorded enter the territory of Egypt with the imported plant materials. This is a pioneer work for weed risk analysis in Egypt, where 5000 samples of imported grains in the period from 2009 to 2017 were used to detect weed seed consignment in imported grain shipments as well as to estimate weed risk assessment of the main of some weed species, ragweed (Ambrosia artemisiifolia), giant ragweed (Ambrosia trifida) as alien weed on agriculture in Egypt. Weed risk analysis scores for the genus of Ambrosia, it has three species, common ragweed (Ambrosia artemisiifolia), giant ragweed (Ambrosia trifida) and perennial ragweed (Ambrosia psilostachya) were frequently detected in imported wheat, maize and sorghum seeds and seen to possess the highest potential phytosanitary risk for Egypt. These weed species were not found in Egypt and achenes of these weeds were detected, they had the ability to germinate and to produce viable seeds under growth chamber and wire house conditions. The probability scores for the introduction of Ambrosia spp. in Egypt is 6.3 and is considered relatively high in the large quantities of imported grains where they can survive and transit easily after dropping into the soil to germinate causing field infestation and the probability of establishment was relatively high economic impact showed a degree because 6.0 causing an economical loss by, and the Ambrosia spp. because of these reasons imported plant materials, i.e. wheat, maize and sorghum should be completely free of Ambrosia spp. achenes by screening through quarantine work to prevent its entrance to the territory of Egypt. .