| Ground Water Quality Index (GWQI) has been used in the present study to evaluate suitability of groundwater and drainage water for irrigation purposes in Al-Yusufyiah area - Baghdad Governorate – Central Iraq. This was carried out by subjecting thirteen groundwater samples and three samples from drainage water for comprehensive physic-chemical analysis. This technique requires several parameters to satisfy the calculation. These parameters include physical and chemical characteristics of water samples such as: pH, Electrical Conductivity (EC), Sodium Adsorption Ration (SAR), Total Dissolved Solids (TDS), Calcium, Magnesium, Sodium, Potassium, Bicarbonate, Chloride, Nitrate and Sulfate. The results show that Al-Yusufyiah ground and drainage waters unsuitable for irrigation purposes except five samples of ground water are doubtful which are (W1, W2, W7, W8 and W9). The high value of GWQI has been found to be mainly due to the higher value of TDS, EC, Ca+2, Mg+2, Na+, Cl-, and SO4-2. Such waters are not suitable for irrigation purposes under normal condition and further action for salinity control is required. |