A field study was conducted in Bustan area to determine the suitable length of PE pipes built-in drippers) with outer diameters of 15.6 mm, 16mm and 20 mm at 50 cm spacing between drippers. The average emitter discharges ranged from 2.0 to 2.5 I/h at operating pressure 1.0 bar. Three random samples were tested according to the described methods in ISO 9260 (1991) and AEnRI Standard Coding: IR/DR/EM/TEST/ (2002). The tested samples were: 1- PE built-in dripper 15.6 mm/ 50 an and nominal disdriarge 2.2 I/h. 2- PE built-in dripper with 16.0 mm /50cm and nominal discharge 2.2 Vh. 3- PE emitter built-In dripper 20/ 50crn and nominal discharge 2.5 I/h. The results showed that: 1- In case of pipe 15.6/13.8 mm (0.D/ I.D.), the maximum length under test conditions was 140 m of pressure drop from 1.5 bar to 1.0 bar. The emitter showed a turbulent characteristic according to observed equation q = 2.5073 17.93.i . However, at conventional design condition of allowable pressure drop 10 % from inlet pressure of 1.0 bar , the suitable design length was 75 m with discharge drop 2.5 to 2.38 I/h. 2- In case of drip line emitters with 0.0/ I.D 16/13.8 mm of fully self compensating, the suitable design length reached to 140 m according to field data which showed an almost constant discharge of about 2.2 I/h at inlet pressure 1.0 bar according to observed equation q = 2.2 h'"5". 3- In case of pipe 20.0 mm O.D. and 17.6 mm LD the suitable length 160 m, at inlet operating pressure 1.5 bar decreased to 1.0 bar resulted with turbulent flow, q = 2.694571e493i at the allowable variation of the pressure 10.0% from inlet pressure (1.0 bar) and discharge 5.0%. The discharge ranged between 2.70 I/h and 2.56 I/h for length 120 m.