Abstract. Research in the 80s of the XX century aimed at changing the hydromodular zoning of irrigated lands of the Khorezm oasis in Uzbekistan, the distribution of irrigated lands by hydromodular regions and the definition of scientifically based irrigation regimes for cotton in each hydromodule region. This article presents the results of scientific research on the implementation of hydromodular zoning of irrigated lands of Khorezm region, the distribution of irrigated lands by hydromodular regions and the definition of scientifically based irrigation regimes for cotton in the main hydromodular regions of Khorezm region. Moreover, it provides information on the study of hydrogeological conditions, the definition of irrigated lands in the new hydromodular areas of the oasis. Irrigated lands of Khorezm region belong to one soil-climatic zone - desert zone, three soilameliorative areas within this zone. For the first time electronic distribution of irrigated lands of Shоvоt and Gurlan districts of Khorezm region on the basis of geographic information system (GIS) technology, using the data of soil-lithological sections and observational wells maps were created. When irrigating cotton in the most common hydromodule regions VII, VIII and IX in the region cotton, while maintaining the pre-irrigation the soil moisture at the level of 70-80- 60% LSMC (lowest soil moisture capacity), and cotton is grown at 3856 m3 / ha (VII), 2789 (VIII) and 2203 m3 / ha (IX) irrigated according to seasonal irrigation norms; 35.0, 38.9 and 39.8 С/ha of cotton, with a minimum of one quintal for growing cotton: 55.4; 71.7 and 110.2 m3 of river water is consumed.