Rangelands is one of the most valuable national capitals of some countries, not only from forage production perspective, but also from a variety of other aspects. Iran’s rangelands have taken retrogressive trend due to overcapacity utilization caused by some reasons such as ignorance of rangelands’ non-forage values. In this research we tried to valuate two functions of rangeland ecosystems including water conservation and erosion control to be used for more accurate appraisal of nomad’s utilization. Vegetation cover, production, grazing capacity, condition and trend of rangeland ecosystems were measured and estimated before and after livestock presence. Curve number method and MPSIAC model were used before and after livestock grazing to estimate the effects of livestock on water conservation and erosion control functions, respectively. Replacement cost method was employed for economic valuation of the functions. Also all the information about nomad’s costs and incomes were collected using survey method and corresponding questionnaires. Results reveal that despite the grazing capacity of this rangeland (3159 heads), 51,300 livestock are grazing on this area which has caused the condition of the area to fall from poor to destroyed state. Regarding this pressure on rangelands, the amount of runoff from a rainfall with 2-year return period and also the amount of soil erosion has increased by 939,603 and 14,732 cubic meters, respectively. The economic damage on water conservation and erosion control functions was calculated about 25790000000 Rials. Given that only 37.23% out of the total number of livestock in the region are related to nomadic livestock, the nomad’s share in the losses is 9600000000 Rials. Total annual profit of 90 nomadic herders was estimated 19510000000 Rials and the share of each household is about 216770000 Rials, annually. Also the costs of rangeland forage was calculated and the share of nomadic herders was determined in order to calculate the annual economic turnover of rangeland ecosystems. Based on the results, the share of rangeland forage in total costs of the utilization system (if they should pay) is equal to 1,778,300,000 Rials (2.14%). Regarding this ratio, the nomad’s income from the rangelands will be 2158000000 Rials. Accordingly, the net profit of nomad’s from rangeland ecosystems is only 418000000 Rials, which in comparison to the damages on ecosystem functions (9540000000 Rials) is negligible. This fact shows that however current nomadic utilization system could be financially justifies, but it is not reasonable from the economic perspective and should be revolutionized. Keywords: Benefit-cost analysis, Nomads, Ecosystem functions, Economic valuation, Khafr-Sivar Semirom.