In recent years, deficit irrigation has been widely investigated as a valuable and sustainable production strategy in Egypt. Hence, the present investigation was conducted in a clay loam soil at a private farm near Mansoura city, Dakahlia Governorate, Egypt, during the two summer seasons of 2008 and 2009 to investigate the effects of three irrigation intervals (8, 12 and 16 days, from first irrigation), spraying kaolin at (0, 3 and 6 %) as antitranspirant at 25, 40 and 55 days from planting and their interactions on growth, yield, fruit quality and water use efficiency of summer squash cv. Eskandrani. Results indicated that irrigation every 8 days throughout growing season resulted in highest  foliage weight, leaves weight per plant, mean fruit weight, total fruit yield/fed., marketable yield/fed. and seasonal applied water in both summer seasons. On the contrary, increasing irrigation intervals from 8 up to 16 days caused significant increases in leaves dry matter percentage, total soluble solids and dry matter percentage in fruit and water use efficiency in both seasons. On the other hand, all studied characters except leaves dry matter percentage, dry matter percentage in fruit and seasonal applied water were significantly increased with increasing kaolin levels in both seasons. The interaction effect between irrigation intervals and kaolin levels was significant for all the studied parameters in both seasons. The highest net return was observed with plants watered every 8 days and received kaolin at 6% concentration followed by watered every 12 days and received kaolin at 6% concentration that had higher benefit: cost ratio. From the economic and nutritional point of view, it could be concluded that irrigation every 12 days intervals combined with spraying kaolin at 6% concentration to summer squash cv. Eskandrani might gave the chance for increasing water use efficiency and produce satisfactory and good marketable fruit yield under similar conditions of this work.