The development of the slaughtering industry till the Song Dynasty gradually showed a trend of specialization.The production,processing and selling of meat food were gradually divided and developed into separate industries.The structure of slaughtering industry began to change greatly,and large-scale employment emerged,with brokers ending up witnesses to the end-point meat trade.Though there was a gradually enlarged income gap between butchers in their industry, the income level of butchers is not low compared to those in other industries.