Arid ecosystem conditions are characterized by water scarcity offer as well due to limited water resources, low irrigation efficiency. Therefore, more efforts had to be carried out in order to find out suitable solutions for this problem and maximizing irrigation unit net return. Therefore, the aim of this investigation was to build; verify; and validate of a developed computer program under arid conditions of Egypt. A developed computer program, ISM-ES (Irrigation Systems Management-Expert System), had been coded by using visual basic 2013 programming language and access software for building up the required database. The developed rule based ES is running under windows media. Moreover, SCWU (seasonal crop-water use); SCWR (seasonal crop-water requirements); WSP (water saving percentage) and IWP (irrigation water productivity) processed as judgment indices in the verification and validation processes. Results revealed that the developed ISM-ES resulted in improving the crop-water production as function of tomato crop and maximize the water unit productivity compared with other ES (IMOC-ES) and conventional treatment based on FAO concepts by using program (CropWat 8.1). Results indicate that SCWR had been decreased under investigated ISM-ES compared with the conventional method approved by FAO at all times of investigations. Meanwhile, there is no significant difference between IMOC-ES and conventional method approved by FAO. On the other hand, by applying the (ISM-ES) to determine the SCWR found that a significant difference. Moreover, data analysis indicated that the developed ISM-ES and IMOC-ES had saved the irrigation water with about 20.49 and 4.88 % compared with conventional method approved by FAO, respectively.