Optimal irrigation and nitrogen management remains a major challenge for improving water use efficiency, nitrogen use efficiency, and vegetables yield in Egypt. The effect of three irrigation intervals (8, 12 and 16 days, starting after first irrigation), three nitrogen fertilizer rates (60, 75 (control) and 90 kg/fed.) and their interaction on growth, fruit yield, nutritional status, water use efficiency and nitrogen use efficiency of summer squash cv. Eskandrani were studied in two experiments conducted in a clay loam soil at a private farm, Mansoura district, Dakahlia Governorate, Egypt, during the two summer seasons of 2006 and 2007. Results indicated that irrigation every 8 days throughout growing season resulted in higher foliage weight, number of leaves and leaves weight per plant, total fruit yield/fed., marketable yield/fed., mean fruit weight, seasonal applied water and agronomic efficiency of nitrogen (AEN) in both summer seasons. Early fruit yield/fed. and K concentration in leaves were highest with the intermediate interval (12 days) in both summer seasons. On the other hand, there were insignificant differences between irrigation every 8 or 12 days intervals in N, P, and K uptake by plant in both seasons. Water use efficiency (WUE) and N and P concentration in leaves were highest with irrigation interval at 16 days in both seasons. All studied characters except AEN were significantly increased with increasing “N" rates, whereas there were insignificant differences between 75 and 90 kg N/fed. in either P concentration in leaves or WUE in both seasons. AEN was significantly decreased with raising N rates in both seasons. The interaction effect between irrigation rates and “N" levels was significant for all the studied parameters in both seasons. Generally, it could be concluded that irrigation every 12 days intervals combined with application of 75 kg N/fed. to summer squash cv. Eskandrani fields might gave the chance for increasing water and nitrogen use efficiency and produce satisfactory and good marketable fruit yield with minimizing environmental impact of over-fertilization.