The article provides information on the usability of groundwater with different degrees of mineralization for irrigation in water supply. Research shows that groundwater with a mineralization rate of up to 1.5 g/l can be used freely without any additional measures in water supply. Most of the quality indicators of waters with a mineralization rate of 1.5 g/l to 3.0 g/l are within the norm, but some quality indicators are outside the acceptable limits. Therefore, it is necessary to take additional measures to improve their quality when using such water. However, in crisis situations, groundwater with a mineralization rate of up to 3 g/l can be fully used for water supply. The quality of water used for irrigation must meet 2 main requirements: 1. Irrigation water should not harm the biological development of plants, productivity, and product quality; 2. During irrigation, the process of repeated salinization and solnetzicity should not occur in the soil and should not damage the fertility and productivity of the soil. The quality and suitability of irrigation water are classified according to their degree of mineralization: If the degree of mineralization of water is 0,5 g/l, water is fully suitable for irrigation, 0.5-2.0 g/l - suitable, 2-5 g/l - less suitable, >5 g/l - irrigation is dangerous. It is recommended that the temperature of the irrigation water be 14-200. Water is considered completely suitable for irrigation when pH = 6-8.5, conditionally suitable when pH > 8.5, and unsuitable when it is pH<6 and pH>9.