The marshes of Iraq are located in the southern part of the country with small portion that is located in Iran. They cover an area of about 15000-20000 km2. The marshes consist of hydraulically connected shallow lakes and scattered ponds. Three major marsh areas are considered the core of the wetlands of Iraq: (i) Al Hammar Marshes; (ii) the Central Marshes and (iii) Al Hawizeh Marshes. During the last two decades of the twentieth century, the marshes were subjected to natural and deliberate dryness and destruction and their area reduced to about 10% of the original area. The Iraqi regime in the early nineties of the last century has cut off the marshes’ inflow supplies and dried out the majority of the core marshes permanently. The regime has constructed numerus dykes, manmade cannels to implement the draining the drying process. Efforts are underway to restore the dried marshes. The restoration process requires sustained surface water supplies to re-flood the area and sustain it. Abu Zirig is a small marsh that is part of the Iraqi Central Marshes (ICM). The marsh constitutes a natural depression at the mouth of al Gharraf River. It is situated about 40 km to the east of Nassiriah city. The marsh was one of the marshes dried by diverting flows away from it via manmade embankments. Abu Zirig was part of the re-flooded marshlands. The embankments were removed immediately following the fall of Saddam’s regime on the year of 2003. Its restored area was about 120 km². The marsh consists of two parts separated by manmade dyke; upper and lower parts. This paper is an attempt to study the hydrology of the Abu Zirig Marsh, specifically, the water budget. Determination of water budget component in situ (i.e. the marshes area) is needed to evaluate the restoration process. It was found that the only inflow source was surface water flowing from al Gharraf River. Losses were to infiltration and evaporation. The marsh was considered operating on steady state, so that change in storage during the study period was zero.