One of the significant today's concerns is the problems wastewater generated by various industries. Steel industry is one of the most consumer of water. Restoring or purifying wastewater of such industries, can save a huge volume of water. One of the most good candidates for water saving in steel industry is final rinsing water at pickling unit. In Mobarake Steel Complex unit, the steel pieces are washed by DM water after acid pickling to remove all traces of impurities on the surface of steel pieces. The pure rinse water is polluted with the latest remained acid and iron chloride scales and discharged as wastewater with electrical conductivity about 16000 to 55000µS/cm and pH about 0.55 to 1.3. The volume of this wastewater is about 20-25 cubic meter per hour. The main purpose of this experimental work was to purify and recycle this wastewater to pickling unit by ion exchange method. To remove Fe(II) ion from this wastewater, two methods were used: cationic resin and neutralization with caustic soda methods. For further treatment, an advanced resin method, called APU, with weakly basic anion resin has been employed. During this experiment hydrochloridric adsorbed by resin and iron chloride discharged from resin bed. During this research the effect of pH, electrical conductivity have been investigated.Optimum residual time of operation was 5 minute, Optimum ratio of wastewater volume to resin volume 3 to 2, and the volume of water of resin regeneration was about 1bed volume. The recovered water of this research has EC less than 300?S/cm and its iron concentration is less than 300ppm while its pH is about 6. This recovered water had requirement condition of pickling unit of Mobarake Steel Complex. In the next step of this research, the combination method of using neutralization and anionic resin has been examined. In first step, neutralization, by adding caustic soda 100% of iron had precipitated and acidity was removed. The final results shows that using this combination method produced water with electrical conductivity about 30µS/cm and pH about 7.5, such a desirable quality that can be recycled in pickling unit. The combination method had better results but required caustic soda for regeneration and more water was consumed during regeneration. Keywords: Ion exchange resin, waste water treatment, electrical conductivity, pickling unit of Mobarake Steel Complex, steel sheets