Agriculture is inherently sensitive to weather and climate especially water supply and heat changes. Adaptation of an appropriate economic management strategy is one of the likely decisions to cope with the impacts of climate changes. The effect of the potential impact of three sowing dates; first sowing date (16th November, FSD), second sowing date (1st December, SSD) and third sowing date (16th December, TSD) on two wheat cultivars (Giza 168 and Sakha 93) under three levels of water stress (irrigation every: 10; 15 and 20 days) was studied at the Farm of Environmental Agricultural Sciences Faculty, El-Arish, during two winter seasons (2009/2010; 2010/2011). Results showed that the Second Sowing Date (SSD) gave superiority of wheat grain yield and most of its components, in response to increasing heat temperature at anthesis stage. Most of growth characters, grain yield and its components of Sakha 93 cultivar were greater than Giza 168 under both stressed and non-stressed conditions; this cultivar could be adapted to heat and water stress more than the other one in relation to its genetic stability under unfavorable conditions and its positive response to late sowing date. Water Consumptive Use (WCU) means by Sakha 93 was higher than those of Giza 168 under all water stress levels; superiority was recorded for 10 day interval.