Sit up, operation and maintains costs of drip irrigation system are high with respect of other modern irrigation systems. This is a limited factor to spread the drip system especially in new reclaimed lands .Using lower water distribution uniformity should reduce these costs. The reducing cotton yield and quality as using lower uniformity of the system is unclear. The field experiments were conducted at Ideal farm of Oil crops. West No. baria area, Behera governorate, in the 2010 and 2011 grown seasons of cotton. Extra long staple variety (Giaz92) is used .The cultivated area is about 31 feddan. Full line of mechanization was used. Two types of cotton picker (4 row self propelled machine and 2 row trailed machine) were used. Christiansen uniformity coefficient (CU) of irrigation approximately 93%, 85% and 67% and three irrigation levels of 100% WR, 90%WR and 75%WR were used. The water requirement WP determined according to DACOM irrigation management by using soil moisture properties, weather station, weather forecast and remote sensing by using satellite technology. 1-Higher system uniformity within irrigation levels produced a more suitable plant height for mechanical picking, yield and more picking efficiency than lower system uniformity 2- The mechanical picking was reduced picking cost by 70% compared to manual picking.3- The system uniformity of 85% and water requirement of 23801m3/fed should be used of drip irrigation system and suitable for mechanical picking.4- The picker does not adversely affect the grad and lint color after pre cleaning of seed cotton used and fiber quality such as fiber length, fiber strength, length uniformity micronaire and elongation.