As block chain accelerates its integration into all areas of social and economic development，its application value continues to gain prominence and the associated risks are gaining attention. In this context，government departments in various countries continue to introduce relevant policies in 2021 to keep up with the pace of change. These policies cover three major themes：block chain industry applications，cryptocurrency regulation，and the issuance of digital currency by the People’s Bank of China. Driven by policies，countries have formed different transmission effects in block chain industry ecology construction，block chain infrastructure building，block chain application activity，hot application areas，and application achievements. From the multi-dimensional comparative analysis at home and abroad，it can be seen that Chinese government departments have established the most systematic and perfect block chain policy environment in the world. At the same time，the block chain technology and industry landscape is still under rapid change，and domestic block chain policies will be continuously adjusted and optimized accordingly.