Introduction: Water scarcity in arid and semi-arid regions is one of the challenges for providing forage. Considering the role of forage crops as raw materials in providing protein and dairy products, maintaining the health of the society and food security of Iran, it has a heavy mission to increase the population and improving the level of health and nutrition of the people. So, it is the responsibility of the policymakers of the production sector to plan more precisely, use all the empty capacities and increase the productivity of available resources with the least reliance on imports which can be an effective step in meeting the food needs of the society. Various solutions have been proposed for producing the forage with less water consumption. One of these solutions is the production of forage in greenhouse conditions. This is especially important in the case of greenhouse infrastructures, which are not economically viable for various reasons, including increased salinity of irrigation water, the prevalence of pests and diseases, and imbalances in soil nutrients. However, there is a hypothesis that given the many advantages such as high-water savings and increased production, the greenhouses can be dedicated to forage cultivation, especially during free times when other plants are not being cultivated there. It is believed that in a greenhouse system, while producing high forage compared to open space, significant savings can be made in the use of water resources, energy, consumption of inputs such as fertilizer, pesticides, and labor costs. This study aimed mainly at evaluating the economic feasibility of forage production using corn and sorghum forage plants in the greenhouses in order to diversify the greenhouse production. In this context, an economic comparison with common greenhouse crops (i.e. green cucumber and tomato) was made.  
Materials and Methods: To assess the economic feasibility of forage production under greenhouse conditions (with plastic cover), a study was conducted in Yazd province of Iran during 2021-2022 in a 1,000-square-meter greenhouse unit. The economic analysis of the study was evaluated using the future value method to compare incomes and costs. The study did not include all cost items, including the fixed cost of greenhouse construction. Therefore, it was not possible to economically evaluate the net income of each of the two methods of greenhouse cultivation of forage crops or the production of the above-mentioned common greenhouse crops and calculate their economic justification separately. However, it was possible to make a comparison between the incomes obtained and the variable costs spent between two methods of greenhouse cultivation of forage crops or those common greenhouse crops. Thus, if the difference in the future value of the profits of two greenhouses of common crops compared to the forage crops was greater than zero, the greenhouse production of cucumbers and tomatoes would be better. Conversely, a negative difference in the future value of profits indicated an increase in the costs of producing the cucumbers and tomatoes over the forage crops. 
Results and Discussion: The study results showed that under the  greenhouse conditions, sorghum was produced in a yield of about 65,000 kg per thousand square meters of greenhouse in one year with the possibility of six times of cropping. This production rate was at least five times the production of the plant in the field. In the case of corn, with the possibility of planting three times of the plant cultivation during one year in the greenhouse, 27,000 kilograms of forage were produced per thousand square meters. In addition, the profit difference between the production of corn from cucumbers and tomatoes at three interest rates of 10, 15 and 20 percent was 1229511250, 1404908281 and 1596240000 IRI rials per thousand square meters, respectively; and the profit difference between the production of sorghum from cucumbers and tomatoes at these interest rates was 726060500, 829637312 and 942624000 IRI rials per thousand square meters, respectively. Thus, the production of forage crops was found to be less profitable than cucumbers and tomatoes. Therefore, the economic evaluation of forage production under the greenhouse conditions, considering current costs (excluding fixed costs and greenhouse construction), yield and income in 2024, showed that in the greenhouses where the annual production of cucumbers and tomatoes was less than 19804 and 25207 kilograms per thousand square meters, there would be an advantage in producing corn and sorghum, respectively.  
Conclusion and Suggestions: Based on the results of this study, it is suggested that the greenhouses established during free times that are not under common greenhouse crops should be dedicated to the forage cultivation, due to many advantages such as high-water savings and increased forage yield. The results of the economic evaluation comparing the production of cucumber and tomato crops in a common greenhouse compared to the greenhouse cultivation of forage crops indicated that the difference in economic profit was towards the production of cucumber and tomato, unless the average yield of these crops was less than 19804 and 25207 kilograms per thousand square meters; in any case, the cultivation of forage crops (i.e. corn and sorghum), respectively, is recommended.