Nowadays fossil rooted fuels used in the internal combustion engines being exhausted and taking form harmful exhausted gases conclusion of burning these fuels soiling environment have cause to increase investigations about alternative fuels used in the internal combustion engines. If a fuel use in an internal engine, that can be easily evaporate, easily mixed with air, get high energy, easily burn, easily obtain. Liquid hydrocarbon fuels which obtained in fossil (petrol), includes nearly all these properties. Because of this, diesel and gasoline which are the famous petrol products raise the first line. By this time, petrol reserves limited and not separated on regularly. And by the extremely usage of these, that causes various local air currents, air pollution and potential climatic currents. Lots of various alternative fuels were attempted since diesel and gasoline become a fuel in internal engines. Lots of these alternative fuels get low emissions than diesel and gasoline. But that can not found market place because of these limited reserves and higher prices. Nowadays, few of alternative fuels use as a commercial mark. It is necessary using alternative fuel in vehicles because of high petrol price and air pollution is a result of using fossil fuels in vehicles. Although natural gas (NG) is fossil fuel but in gas form is cleaner than petrol and diesel, and has large reserve than petrol. Because of these reasons NG becomes an important alternative fuel. Unfortunately, storing the NG as Compressed Natural Gas (CNG) form brings many problems. The most important problem is especially in small vehicle like cars; 200 bar resistant tanks are heavy and big volume. As a result of this, the vehicle’s distance of range using CNG is different according to tank volume that is about 150 km. However, storing the NG as Liquid Natural Gas (LNG) form in the same tank volume, the tank’s weight becomes lower, by the same time distance of range approaches the petrol using vehicles. In this study, we work at the properties of natural gas (LNG) and the usage of NG in internal engines. Experiments were studied at Erciyes University Mechanical Engineering’s Engines Laboratory. Ford brand, 105 Hp, 1800 cc motor was used in experiment. Exhaust emissions was measured in SUN MGA 1500 gas analyser.