Oman is a country that is mostly dry and hot, with daily maximum temperatures easily reaching 40°C or more during summer. The Oman weather therefore renders conventional open field agriculture almost impossible. The sustainable future of agriculture in Oman and other similar desert countries will therefore depend very much on the adoption of land and water saving technologies such as greenhouses and soilless culture or hydroponics. Soilless culture (Hydroponics) is the technique of growing plants without soil with their roots immersed in nutrient solution. Among factors affecting hydroponic production systems, is the nutrient solution temperature which is considered to be one of the most important determining factors of crop yield and quality. The aim of this research is therefore to investigate the economic effect of cooling nutrient solutions temperature technique on cucumber output. Four nutrient solutions temperatures are investigated and a Cost Benefit Analysis is undertaken. Results indicate that all the four cooling nutrient temperature yields positive returns (benefits) above variable and total costs for the two years of this experiment. Cooling nutrient temperature (22ºC) yields higher returns than the other treatments followed by treatment (25ºC), (28ºC) and then the CONTROL treatment. Returns for the second year are higher than the first year. Therefore treatment (22ºC) was observed to be the best overall producing the highest return above variable and total costs. It is therefore considered the best alternative for cucumber growers.