On October 29, Xinhua News Agency issued a document stating that the blockchain has become the hottest part of the A-share market in these two days. In line with the secondary market, listed companies have recently set off a wave of “chaining”. A number of listed companies such as Meida Digital, Aikang Technology, Meiyingsen and Haoyun Technology have disclosed the latest developments in the development and application of blockchain technology. According to industry insiders, there are quite a few listed companies that have begun to dig deep into the blockchain, but it does not rule out the possibility of some companies being "hot". The concept of blockchain is extensive, and the breadth and depth of participation of listed companies vary, and there is a large gap in the ability of technology application and profitability. In this regard, investors should pay attention to the study of the company's fundamentals, grasp the investment opportunities while avoiding blindly "follow the wind."