What are the pillar industries in China?

The fifth economic census has provided the answer, categorizing the main industries into three major pillars and eight minor pillars based on total revenue and employment of legal entities.

Three Major Pillars:
Machinery, Transportation Equipment, Electronics, and Other Equipment:

Total Revenue: ¥53.35 trillion
Employment: 41.74 million people
Construction and Real Estate:

Total Revenue: ¥56.4 trillion
Employment: 65.61 million people
Wholesale and Retail, Transportation, Warehousing, and Postal Services:

Total Revenue: ¥167.3 trillion
Employment: 69.09 million people
Eight Minor Pillars:
Information Transmission, Software, and IT Services:

Total Revenue: ¥15.2 trillion
Employment: 15.18 million people
Financial Industry:

Total Revenue: ¥17.3 trillion
Employment: 12.48 million people
Electricity, Heat, Gas, and Water Production and Supply:

Total Revenue: ¥12.9 trillion
Employment: 4.78 million people
Leasing and Business Services:

Total Revenue: ¥16.1 trillion
Employment: 39.07 million people
Refining, Coking, and Chemical Products:

Total Revenue: ¥23.06 trillion
Employment: 13.07 million people
Metal Smelting, Processing, and Products:

Total Revenue: ¥22.74 trillion
Employment: 11.46 million people
Food and Tobacco:

Total Revenue: ¥11.62 trillion
Employment: 8.38 million people
Agriculture (estimated as a minor pillar):
Agriculture might also be considered a minor pillar, but its scale may have been underestimated due to the exclusion of individual businesses. According to the Statistical Yearbook, in 2020, the total output of agriculture, forestry, animal husbandry, fishery products, and services reached ¥13.31 trillion, employing over 100 million people.

Of course, further segmentation is possible. The categorization here combines departments with similar directions.