From the perspective of practical progress, most of the applications of blockchain technology in commercial banks are still being conceived and tested, and there is still a long way to go before they can be used in life and production, and there are many difficulties to obtain the recognition of regulatory authorities and the market, mainly including:

（1） Restricted by current concepts, systems and laws. The characteristics of decentralized, self-management and collective maintenance of blockchain have subverted people's production and life style, weakened the concept of state and supervision, and impacted the current legal arrangements. For these, the whole world is completely lack of theoretical preparation and institutional discussion. Even bitcoin, the most mature blockchain application, holds different attitudes in different countries, which inevitably hinders the application and development of blockchain technology. Obviously, there is still a long way to go to solve such problems.

（2） At the technical level, blockchain still needs a breakthrough. Blockchain application is still in the initial development stage in the laboratory, and there is no intuitive and available mature product. Compared with Internet technology, people can use browsers, apps and other specific applications to browse, transmit, exchange and apply information. However, the blockchain obviously lacks such breakthrough applications and faces high-tech barriers. Another example is the problem of block capacity. Because the blockchain needs to carry all the information generated before replication, the amount of information in the next block is greater than that in the previous block. In this way, the block write information will increase infinitely, and the problems of information storage, verification and capacity need to be solved

（3） Competitive technical challenges. Although many people are optimistic about blockchain technology, we should also see that there are many technologies that promote human development. People will apply the technology which is more convenient and efficient. For example, if the blockchain technology is applied in the communication field, the information is sent to everyone in the whole network every time, but only the person with the private key can decrypt and open the letter, so the security of information transmission will be greatly increased. Similarly, quantum technology can also be achieved. Quantum communication - information transmission using quantum entanglement effect - also has the characteristics of high efficiency and security. In recent years, it has made great progress, which has a strong competitive advantage for blockchain technology.