This research is conducted on Erbil basin, it is located in northern part of Iraq, the basin is composed of three main sub-basins which are: Northern part (Kapran), Central sub-basin and Southern part (Bashtepa) respectively. The total area of three sub-basins are approximately (3,200 km2). The main sources of aquifer recharge in the study area is depends on precipitation. The article estimated the percentage and amount of water budget elements for the selected basin. Therefore, the paper evaluates the obtained climate data form Erbil meteorological station for (25 years) to evaluate the water budget in the study area. The main objective to assess the Erbil basin water budget and determine amount of the each parameters related to the study area. Based on the results of this study data analysis the amount of the mean monthly temperature (18.94 C̊), and sun shine (8.18 hr/day), the average relative humidity is (47.82%), the evaporation percentage is (54%) of the precipitation. The study concluded that the amonut of the rainfall data is (394.65mm) and the percentage of precipitation over Erbil basin is (100%), the Recharge into groundwater is (24.23%), the Runoff and Evporation are (21.77%) and (54%) respectively.