Abstract: It is essential to apply big data and big data thinking to governmental governance so as to improve governance capability and modernize governance system. However, governments of different levels are faced with multiple practical limitations in actual operations, such as invalidity of data, lowpotency of data, the blockade caused by isolated data islands and the threat of data security. Blockchain, an emerging technology in recent years, is a good solution to these problems. An innovative combination of multiple technologies such as P2P networking technology, consensus mechanism, asymmetric encryption algorithm and smart contract, blockchain has unique advantages including conferring value to data, decentralizing technological procedure, guaranteeing data security and presents a new pattern of trust. In this context, blockchain, based on abovementioned technologies, helps improve the quality of data that are needed by and fundamental to governmental governance. It also promotes mutual trust among different levels and departments of governments and between governments and social groups, thus achieving data sharing and improved governance. Besides, blockchain can guarantee the security of data which is closely associated with government legitimacy and public trust. To sum, blockchain, if applied appropriately, will become an effective tool in solving the digital predicaments in governmental governance in the era of big data. However, it should be kept in mind that blockchain technology is still at its initial stage and more improvements and observations of its application effects are needed, so its function in governmental governance should not be exaggerated. 

Key words: Key words： blockchain, big data, governmental governance；public trust