This investigation was carried out during three successive seasons of 2004, 2005 and 2006 to evaluate the effect of different sources of organic fertilizers such as : compost, town refuse and cattle manure on yield, berry quality, both nitrate and nitrite and NPK content in leaf petiole of Thompson Seedless grapevines. The data also reveal that, adding organic fertilization in Thompson Seedless vine yard under low level 40 units of nitrogen/ vine increased yield per vine, average cluster and berry weight than the vine which left without organic fertilization received only to mineral fertilization at 60 units per vines. Furthermore, using compost or cattle manure at 5 kg/vine were more pronounced for increasing yield per vine and per feddan than the other organic fertilizers. Since, these treatments gave a higher cluster and berry weight, but reduced the values of both nitrate and nitrite. So, it become safe to be used for our fertilization program of Thompson Seedless grapevines under similar conditions.