An introduction to the top natural gas companies in the world. : Most of the world's biggest producers of natural gas are global energy giants with worldwide oil and gas operations spanning the full range of upstream and downstream activities. When production is viewed by country, the U.S. is the top producer of natural gas followed by Russia, Iran, Qatar, China, and Canada. Here's a look at the top producers of natural gas, along with some key facts about each company. China National Petroleum (CNPC) is China's largest natural gas producer.