The research aims to measure the productive and economic efficiency of farms working in this activity. The statistical measurement of the production functions of the barley crop under the rain irrigation system showed that the overall production flexibility under the rain irrigation system amounted to about 1.563 for the first category, compared to about 1.391 and 1.316 for the second and third categories, respectively, which indicates that barley growers under the rain irrigation system produce in The first non-economic stage of the law of diminishing returns, which requires the necessity of intensifying the factors of production used to achieve productive efficiency. By studying the lost income, it was found that the optimal volume of production reached about 1660 kg within the first category (less than an acre), compared to about 1560 and 1452 kg for the second and third categories, respectively. The bulk of the profits amounted to about 2874 kg for the first category, compared to about 3016, 3311 kg for the second and third categories, respectively, as it was shown that the profit margins increased with the increase in the size of the feddan holding. The research recommends expanding the production of barley crop within the lands of central Sinai by cultivating large areas of more than three feddans for the holder, to take advantage of the advantages of abundant production, in addition to maximizing the benefit from rain and torrential water on these areas.