Currently, due to its tremendous availability, the use of municipal solid waste (MSW) as an energy source has received significant attention in China. Moreover, when compared to coal and oil, MSW produces negligible NOx emissions in the atmosphere and generates less ash. Gasification is a promising technology for converting MSW and other low-value feedstocks into fuel gases and chemicals. In this review article, production of synthesis gas (also known as syngas) from MSW gasification is reviewed, and demonstrated to be a clean and attractive option. First, a short review of MSW treatment techniques and their advantages and limitations is presented, and then, the energy potential of MSW for gasification purposes is evaluated. Second, influencing process factors such as temperature, gasifying agents, gasifier type, particle size, and operating pressure are studied in terms of their impact on the resulting gas quality and quantity. Finally, the potential of key commercial catalysts (Ni-based catalysts, natural catalysts (dolomite), and blast furnace (BF)) in tar elimination is evaluated.