Abstarct: Usually the oil production rate is reduced or stopped when passing time and depleting reservoir pressure. Artificial lift system is defined as a system that adds energy to the fluid in wellbore with the objective of initiating and enhancing production from the oil wells. In this research three wells from an oilfield of Persian Gulf oilfields (Reshadat) is selected. The first and second wells are completely stopped production rate and the production rate of the third well is reduced. The purpose of this thesis is designed and optimized artificial lift system by using Electrical Submersible Pump (ESP) in any wells. In this study, the appropriate pump with well’s features is designed by analysis of well and reservoir information by using nodal analysis and helping PIPESIM software. The results of this research show that in first well by selecting pump Reda:S5000N with frequency of 70Hz and 65 stages, the production rate reaches 4968 barrel per day. In second well by selecting pump Reda:D5800N with frequency of 60Hz and 151 stages, the production rate reaches 4998 barrel per day and in third well by selecting pump Reda:J7000N with frequency of 50Hz and 42 stages, the production rate increases and reaches 4777 barrel per day. In continuance, the sensitivity of well production is studied by changing some features of pump and tubing and specified that at any wells, the oil production is more sensitive to pump speed and pump stage.