Blockchain is a decentralized infrastructure widely used in emerging digital cryptocurrencies. With the gradual acceptance of Bitcoin, it has attracted attention and research in this field. Blockchain technology has the characteristics of decentralization, and block data is basically non-tamperable and trustless, so, it is sought after by enterprises, especially financial institutions. Now, it has become a hot spot for research and applications following the Internet of Things, cloud computing, big data and artificial intelligence, and it has been listed as one of the biggest development trends for the next ten years by various researchers. Blockchain has the characteristics of decentralization, consensus mechanism, immutability, smart contracts, etc. Based on the analysis and comparison of the current state of blockchain research at home and abroad, and a brief introduction to the key technologies of the blockchain, this paper addresses the recent application progress of blockchain technology in recent years, and analyses the major current blockchain application problems, look forward to the future application prospects and development trends of the blockchain, and then provides useful motivation and reference for the future research and application of the blockchain.