Cambodia is facing frequent manifestations of dangerous hydrological phenomena - floods and droughts. Over the past 20 years, floods have occurred in 2000, 2001, 2002, 2011 and 2013, and extremely dry years were observed in 2010, 2015 and 2016. The banks of the Mekong, Bassak, Tonle Sap Rivers and the Tonle Sap Lake basin are experiencing a more significant impact compared to other areas of the country. The purpose of the study is to identify and assess the flood zones of Cambodia. Research objectives: 1 - generalization of theoretical and methodological foundations for solving hydrological problems in Cambodia; 2 - identification of the features of the hydrological regime of the territory of Cambodia, based on statistical analysis of hydrometeorological information; 3 - construction of flood zones of the territory of Cambodia based on GIS; 4 - analysis of the results and planning of further research. As a result of the work, a statistical analysis of hydrological and meteorological data was performed, water level security curves were constructed, maps of flooding zones of Cambodia were obtained based on ArcGIS 10.8 for water levels of 1 and 50% security. The most fertile lands are concentrated in the Cambodian floodplains, and therefore historically they have witnessed the highest level of socio-economic development and at the same time are areas of risky farming. The assessment of the factors of damage formation from flooding of territories shows that in the considered areas the maximum areas of flooding of the territory correspond to areas with a high population density. This determines the maximum risks and damages from flooding for the population and economy of the country in the southern regions of Cambodia.