Along with the economic and technological development, fossil energy resources have developed from low efficiency to high efficiency, from high carbon to low carbon. Energy resources substitution will be a long process of transition from an era when fossil energy resources are the main part to another period when new energy resources develop rapidly. Natural gas, which is characteristic of immense resource including conventional and unconventional resources and high reserve-production ratio, has become the significant development moment of low carbon fossil energy resources, and will also become the first energy resource. The utilization of natural gas, which is rather low carbon among fossil energy resources, has given rise to great attention and discussion around the world and natural gas will become the bridge to realize energy resources low carbonization. Natural gas is also new energy resource in China, and has great potential for further development.