In this paper, the actual needs of water to be given to agricultural crops are determined. The paper sample was chosen as agricultural crops (Barley, Clovers, Broad bean, Onions, Mung bean, Yellow corn, Watermelon, Yellow melon, Finally the sesame) in Iraq. In addition, the amount of water lost during the transfer of water to the cultivated land was determined. All this was done using simple linear programming, Multi - purpose linear programming (De novo programming) Using the software program (WinQSB). As the year was divided into four periods to determine water needs during each period, and it was found that the largest water needs were found during the months (April-June) due to overlap between winter and summer season. [ABSTRACT FROM AUTHOR]