Two field experiments were carried out at the extension fields of Ministry of Agriculture at Bini Sweef and Minia Governorate in 1998/1999 seasons. The aim of these experiments were to study the response of onion plant to different sources (Cattle, Chicken, and Pigeon) of organic nitrogen fertilizers at different rates (120, 150 and 180 N units/fed.). The important obtained results are as following: The addition of pigeon and/or chicken manures had the vigor onion plant (as expressed by length of plant, leaves number/plant, fresh and dry weight of whole plant and its leaves and bulb) and the total bulbs yield as will as exportable bulbs .On the contrary the application of cattle manure gave the lowest values of the above mentioned parameters. Also, the chemical constituents of bulb tissues (N, P, K, Mn, Zn and Cu) followed the same pattern of change.  However, the statistical analysis of the obtained data recorded no significant differences within using chicken and/or pigeon manure, regarding to the most of the vegetative growth criteria's. However, the percentages of marketable and exportable bulbs recorded their highest values with using cattle manure if compared with other organic nitrogen sources. With increasing the rate of organic fertilizer addition, the vegetative plant growth characters and total bulbs yield recorded their highest values. On the contrary the poorest plant growth was noticed with that onion plants which supplied the lowest rate (120 N units/fed.). Moreover, the highest exportable bulbs yield as tons/fed. was associated with the addition of lowest rate of organic manures in both experiments. The addition of organic manures at rate of 150 - 180 N units/fed. obtained that bulbs which contained the highest values of the nutritional elements (N, P, K, Mn, Zn, and Cu), but with using rates of 120 N. unites/fed. resulted a  decrease in the chemical bulb constituents.