Seed identification of 40 common weed species belonging to 20 families, and 38 genera that is very necessary for researchers, farmers, seed production industry and detection of weed seeds in imported or exported plant materials in quarantine work was conducted at the Weed Research Laboratory, in Giza. Full mature specimens of weed seeds were collected from the farms of Shandaweel, Sids, El Serw research stations during 2008/2009 winter and 2010 summer seasons. Description was depending on seed surface, colour, size and shape, family name and taxonomical names. Surface type identification of seeds of these species was recorded according to the scheme adapted from Murley (1951). Seeds were scanned and their pictures included in the text. Such seeds were used as a nucleus of weed seed herbarium of Weed Research Laboratory in Giza which will play as a backbone of visual comparison in weed identification process. Seed herbarium is arranged alphabetically according to families, genera and species for identifying unknown weed seeds in imported grains.