The shortage in water supply forced the population to drill their private well and extract groundwater to meet their increasing needs. The area under study is a major agricultural area that supports crops such as wheat, barely, lentil and vegetable and large scale livestock operation The importance of chemical characteristics study of groundwater lies in knowing the effect between the lithological unit and water flow, and naturally concentration of dissolved salts increased due to natural dissolution process.  The chemical characteristics of groundwater samples in Telkaif area north of  Mosul City have been studied through the chemical analysis of (14) water samples to evaluate the quality of groundwater for determining its suitability for domestic and agricultural uses. Physical and chemical parameters of groundwater samples such as electrical conductivity  (Ec), pH, Total Dissolved  Solids (TDS), Na+, K+, Ca+2, Mg+2, HC03-1,   S04·2,   N03-1, CI1  and Total Hardness  (TH) were determined.  Hydrochemical parameters are analyzed graphically by using Piper diagram to show the suitability, type and the geochemical evolution of the groundwater.  Richard (1954) and Wilcox (1955) classifications are also used to show the suitability of groundwater for irrigation. Lithological unit of Al-Fatha,  Injana and Quaternary aquifers were identified and examined from the wells distributed over the area of study. Groundwater of the study area is replenished from rainfall and valleys draining water to the catchment. Groundwater chemistry of the study area indicates that most groundwater samples are of CaHC03  and CaS04 water type, having the high total hardness  (TH) and Total Dissolved  Solids (TDS), and generally low alkaline in nature.