Salt refers to the taxes levied by successive governments in China on the production, transportation and sale of salt. The origin of salt tax is very early. During the Warring States period, Qin set officials to collect salt tax.

However, the name of salt tax first appeared in Guan Bai's records at the end of Han Dynasty. Except for the third year of Emperor Kai of Sui Dynasty (AD 583) to the first year of Kaiyuan of Tang Dynasty (AD 7 13), salt was monopolized or taxed in all previous dynasties. The Salt Monopoly Law of the Eastern Han Dynasty allowed people to make and sell salt, and the government set up salt officials in counties and counties to collect salt taxes.