The aim of this research was to determine the effect of three sowing dates (Nov 20 th , Dec 5 th and Dec 20 th ) on yield and some yield contributing characters of three wheat cultivars namely Gemmiza 10,Giza 168 and Sakha 94 . Two field experiments were carried out in Tag El-Ezz Agricultural Research Station, Dakahlia Governorate, Agricultural Research Center (A.R.C.), Egypt, during the two successive seasons 2007/2008 and 2008/2009. Split Plot Design with four replicates were used. According

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... o the results, sowing dates had significant effect on flag leaf area, number of days to heading, plant height, number of spikes/m 2 ,spike length, 1000-grain weight, number of grains/spike, grain yield and protein percentage. Sowing in Nov 20 th resulted in the highest grain yield and its contributing. Sowing in Dec 5 th cause reduction in grain yield and its contributing estimated by about 22-23 % in both seasons. Sowing in Dec 20 th cause reduction in grain yield about 35-44 % in both seasons.On the other side wheat cultivars significantly differed in all previous mentioned characters. However,the cultivar Gemmiza 10 surpassed both Giza 168 and Sakha 94 cultivars in flag leaf area,number of grains/spike,spike length,protein % and grain yield.Meanwhile, Giza 168 surpassed Gemmiza 10 and Sakha 94 in number of spikes/m 2 ,and 1000-grain weight in both seasons.Moreever,the results exhibited that interaction effect between sowing date and wheat cultivar was significant in all studied characters in both seasons. This results indicated that Gemmiza 10 was the most tolerant one to late sowing until Dec 5 th under these experimental environment.