The research aimed to identify the degree of presence and strength of cooperation and coordination between the Departments of Water Guidance and Agricultural Extension in the rationalizing use of irrigation water in Sharkia Governorate, The study was conducted on a sample 149 respondents from agricultural extension workers and workers in the Department of Land and Water in Sharkia Governorate. The data were collected by a personal interview questionnaire form in beginning of August 2021 until October 2021. The data were analyzed using frequencies and percentages, mean, weighted mean, Pearson correlation coefficient, t-test. The results concluded that the most important sources of information in the rationalizing use of irrigation water are irrigation departments, and reliance on the information of the Central Administration for Agricultural Extension. And the degree of implementation of the advisory and directional activities in the rationalizing irrigation water is high . there is cooperation and coordination between the Department of Water Guidance and Agricultural Extension at rate of 61.2%. . It was also found that the most important ways to strengthen the relationship between the Departments of Water Guidance and Agricultural Extension to rationalize the consumption of irrigation water in the Sharkia Governorate are working on the development of a law or legislation from the state that governs and regulates the relationship between the Departments of Water Guidance and Agricultural Extension, and the work of programs Training with the participation of the two departments to rationalize water consumption and maintain water suitability for irrigation.