Judging from the requirements of modernizing the country’s governance capacity, there are still systematic technical bottlenecks in the governance of public opinion in public crises in China, mainly manifested in the following: massive social opinion data overwhelms traditional public opinion monitoring techniques, making it difficult to understand mainstream public opinion; pluralistic societies are in turmoil, making it difficult to achieve effective emotional mobilization and value leadership; and the increasingly polarized public opinion field makes it difficult to implement effective network intervention. Although far from mature, big data technology provides a lot of momentum to break through these bottlenecks. Relying on massive data on public opinion, in-depth grasping of the inherent laws and modes of dissemination of public opinion in public crises can help promote the improvement of public opinion governance capacity in public crises.