Abstract In the face of energy crisis and greenhouse gas emission reduction, coal to synthetic natural gas (SNG) production attracts increasing attention worldwide. This work proposed a novel coal to SNG plant, in which the high-efficiency coal-steam gasification technology and one-step methanation method are adopted. In this novel system, the air separation unit and water gas shift process can be eliminated. Besides, through the one-step methanation, the CO2 concentration is much higher than the traditional SNG plant and the energy consumption of CO2 separation will be reduced. Via the coal-steam gasification and one-step methanation methods, the SNG output of the novel plant can be significantly improved and the total plant thermal efficiency increases by 15 percentage points.