ABSTRACT Natural gas has the potential to play an important role as a “bridge” fuel in the transition from fossil fuels towards a cleaner energy mix and a low-carbon future. The use of natural gas as a source of energy for electricity generation has advantages over oil fuel and coal. Apart from being cleaner, the use of natural gas for electricity is relatively more competitive than for oil fuel. One of the gas fields in Indonesia that has quite a large gas reserve but has not been utilized is the Sinamar field, which is located in West Sumatra Province. In the plan of development, natural gas from the Sinamar field will be used as fuel for a generator that will generate electricity. The total gas to be produced and to be lifting for 17 years is 10.49 BCF with an estimated sales gas flow rate of 1.72 MMSCFD. The results of the economic calculation from the Upstream business obtained economic indicators such as IRR of 25.7% and NPV of 3.56 MUS$ with a POT of 5.68 years. Meanwhile, from the Downstream business with a lower target electricity tariff with the regional BPP, Gas Engine power plant produces an IRR of 11.87% and NPV of 0.47 MUS$. Financially, the use of Gas Engine technology is more feasible than Gas Turbine Combine Cycle. Technically and economically, the Sinamar Gas field monetization project is feasible to be applied.