The increasing demand for natural gas and growing share of this energy carrier in the world primary energies supply and the necessity of creating added value from gas resources instead of selling them crudely, has made it necessary to use new technologies in this industry for Iran as the world's largest gas reserves holder. In this study we have evaluated the application of the process of gas to liquid products (GTL) conversion technology in Sarakhs special economic zone using Comfar software and in terms of the Net Present Value (NPV) criteria, Internal Rate of Return (IRR) and payback period (PP) and also based on studies carried about Iran in 72 different cases. Based on the findings, the project is merely justified in the case of maximum predicted price for each barrel of crude oil. As expected, the project has economies of scale. The results also show that if the feed cost of production unit is calculated with consumer prices, the project will be profitable even on a small scale and with high investment costs.