The four occupations (), or "four categories of the people" (), was an occupation classification used in ancient China by either Confucian or Legalist scholars as far back as the late Zhou dynasty and is considered a central part of the fengjian social structure (c. 1046–256 BC). These were the shi (gentry scholars), the nong (peasant farmers), the gong (artisans and craftsmen), and the shang (merchants and traders).
The four occupations were not always arranged in this order. The four categories were not socioeconomic classes; wealth and standing did not correspond to these categories, nor were they hereditary.
The system did not factor in all social groups present in premodern Chinese society, and its broad categories were more an idealization than a practical reality. The commercialization of Chinese society in the Song and Ming periods further blurred the lines between these four occupations. The definition of the identity of the shi class changed over time—from warriors, to aristocratic scholars, and finally to scholar-bureaucrats. There was also a gradual fusion of the wealthy merchant and landholding gentry classes, culminating in the late Ming dynasty.
In some manner this system of social order was adopted throughout the Chinese cultural sphere. In Japanese it is called "Shi, nō, kō, shō", although in Japan it became a hereditary caste system. In Korean it is called "Sa, nong, gong, sang" (사농공상), and in Vietnamese is called "Sĩ, nông, công, thương (士農工商). The main difference in adaptation was the definition of the shi (士).
From existing literary evidence, commoner categories in China were employed for the first time during the Warring States period (403–221 BC). Despite this, Eastern-Han (AD 25–220) historian Ban Gu (AD 32–92) asserted in his Book of Han that the four occupations for commoners had existed in the Western Zhou (c. 1050–771 BC) era, which he considered a golden age. However, it is now known that the classification of four occupations as Ban Gu understood it did not exist until the 2nd century BC.