Two field experiments were carried out at Shalakan Exp Sta, National research Center NRC in 1994 and 1.995 season on Giza 75 cotton variety The tested factors were irrigation (I) at 3 depletion levels of available SCII moisture ml: at 40. ED and 80 0/0 SMD and two Planting date (PD), viz. 31 march (Normal) and 30 April (Late) A split plot deSign with 3 replicates was used The studied topics included growth traits, yield attributes yield and water relationship The results showed that irrigation 40% SMD gave significant increase in leaf area index, leaves dry weight and total plant dry weight Leaf weight ratio was rot Significantly affected by irrigation Normal planting date (DD) significahtty exceeded the late one (PD; regarding Wit all studied growth traits The combination between the two facto's significantly affected all the growth attributes where early planting along with frequeat arrigation at 40% SMD promoted cotton plant growth For yield and t3 attr:bu:es. irrigation at 40% SMD The 40 9'0 SMD Significantly surpassed the other two treatments with respect of plant height, boll weight and seed index. cewer. irrzgatlon at 60% SMD produced higher seed cotton yield either per plant or per fed Laze planting showed significant and negative effect on No. of bolls/plant, boll weight and seed index Where. ncrncal planting resulted in Significant increments in seed cotton yield/plant and per fed as well as lint yieldifed The interaction between the two factors gave different resu ts between the two seasons. In the first season irrigation at 60% Sll x normal planting signifi3antty achieved the highest seed c:tton ant tint yieldsi'fed l.‘i‘here, as toe combination 80 % SMD x PDt gave the higher yieldsifed in the two seasons T'ie water consumptive use ranged from 32660 and 3290.0 m°/fed, given in 8 irrigalipns in each season Water use efficzency WUE ranged between D 03 and O 25 Kg‘m‘ The highest water use effiCiency was recorded for early planttno and irrigation at 80 Co SMD