This trials were carried out during the two successive winter seasons of 2008/2009 and 2009/ 2010 at the Experimental Farm, Sids Horticulture Research Station, Agriculture Research Center, Giza, Egypt, To study the effect of the nitrogen sources and rates of anhydrous ammonium sulphate and ammonium nitrate at (30, 60 and 90 kg / fed.) and their combined application, on growth and yield of potato crop.               The highest values of tested parameters were recorded by using anhydrous ammonia at rate of 180 kg N/fed. in both seasons.