The limit value of total sulfur content of gas class one has been lowered from 60 mg/m3to 20 mg/m3byGB/T 17820-2018 Natural Gas, which was released in December 2018.Combined with the analysis of China's national conditions, it can be seen that: 1) at present, China's SO2emission control has witnessed effective result, and the annual average concentration of SO2in the atmosphere of Beijing, Shanghai and other international metropolises has been reduced to less than 20 μg/m3,which is far better than that of Tokyo (57 μg/m3, 2013) in Japan;2)the organic sulfur removal efficiency of the physical and chemical mixed solvent developed by China can reach 90%,but as for feed gas with high mercaptan content, the mercaptan cannot be reduced to less than 16 mg/m3in a single desulfurization process;3)at present, China has not mastered the technical key of "1 + 1" combined dehydration and mercaptan removal process.Moreover, the negative impact on the coordinated and stable development of the natural gas industry caused by the use of such sulfur emission reduction measures at the cost of significantly increasing energy consumption and carbon emission cannot be underestimated;4)currently, except Germany, there is no country in the world adopting the limit value of total sulfur content at 20 mg/m3,and for China's national conditions, even if this indicator is achieved,the annual SO2emission reduction is only 3580t, which is less than 0.4% of the current annual SO2emission reduction;5) there is no internal relationship between limit value of total sulfur content of gasoline and diesel specified by the China V standard and that of commercial gas specified in GB17820-2018, and it is unnecessary to require those two different products, produced by different industries with completely different processes, to have the same total sulfur limit value;6)vigorously developing the natural gas industry itself is an important way to effectively improve the environment.To sum up, this restriction is unnecessary and may bring about many negative effects.