The present study focuses on evaluating the quality of groundwater in Green – Belt project in Al- Najaf Governorate area for human drinking and irrigation. The samples have been collected from five wells, which, have been used to irrigate the plants in the project. Thirteen parameters has been selected for assessment quality of ground water: temperature, pH, electrical conductivity, total dissolved solids, sulfate ion, turbidity, oil & grease, cadmium, lead, chromium, iron, copper, zinc. In addition, the values parameters have been submitted as spatial distribution on map by using GIS. In addition, water quality index for irrigation and human drinking were calculated. Almost all samples have high salinity, which represented as EC., TDS and SO4-2. In addition, the results exceed the standard limits for irrigation and human drinking. O&G was very high concentration in wells GWF4 and five due to upstream AL-Najaf refinery and they are no recommend for drinking or irrigation. Heavy metals in samples were exceeding the limit of human drinking for lead and iron but other metals were within limits except few samples. For irrigation, almost all samples were within limits, but not recommended for fruits. Calculation of IWQI showed that wells GWF1, two, and three located in fair category, which, regarded as moderate restriction and possibility using for irrigation in Green-Belt project and no side effect on human except palms and olive. The values of IWQI in wells GWF4 and 5 are poor and regards as severe restriction which, can not be used due to contain of O&G in water from AL-Najaf refinery. WQI calculation showed GWF1, two and three were categorized poor and may be used as human drinking water with treatment units. Nevertheless, GWF4 and five were unfit for human drinking.