Iran is in a serious freshwater shortage crisis because its major part is located in arid and semi‐arid areas. This research evaluated the groundwater quality in terms of potable and irrigation uses in the wet and dry seasons in the Kazeroon plain, southern Iran. In this study, a total of 408 groundwater samples were gathered from 68 boreholes to measure water quality indices, such as acidity (pH), electrical conductivity (EC), total dissolved solids (TDS), total hardness (TH), bicarbonate (HCO3−), chloride (Cl−), sulphate (SO42−), calcium (Ca2+), magnesium (Mg2+), sodium (Na+) and potassium (K+). Geographical information system technology was also applied to draw maps of spatial changes of water quality parameters. The results showed that groundwater quality indices had the minimum and maximum values of pH (6.9–8.6), EC (414–9,813 μmho cm−1) and TDS (278–6,180), TH (175–3250), HCO3− (152–518), Cl− (5–1950), SO42− (17–2371), Ca2+ (30–681), Mg2+ (12–607), Na+ (1–1303) and K+ (0.8–18) (mg L−1). Based on World Health Organization standards, the results indicated that all of the aquifer water in the plain except for the northern region was of poor and very poor quality for potable usages. Also, the United States Salinity Laboratory diagram showed that the groundwater quality is doubtful for irrigation. Therefore, the cultivation pattern in this plain should be switched towards salt‐tolerant crops.