With the rapid development of Internet media in recent years, the main position of IP promotion and dissemination of urban regional culture has shifted from traditional media to new media mainly based on mobile Internet. This paper takes the viewpoint evolution model as a research tool, decides the best choice for decision-making based on the quality value of the main evidence, and adjusts its viewpoint using Bayes’ rule. The analysis includes both positive and negative perspectives on the issue of promoting regional cultural communication in second and third-tier cities through IP promotion and integrated media. Finally, we discuss the mechanism of the communication of the regional culture of second and third-tier cities through the integrated media and analyze the influence of the integrated media communication effect on the regional culture of second- and third-tier cities through the Bayesian model of improving the evolution of viewpoints. The results show that in the process of evolution, the group of people who agree with the positive view is 0.483, while the group of people who hold the negative view is only 0.223. In addition, ‘Culture X’s’ enhancement through the melting media has resulted in a nearly 1.8 million increase in the number of cultural program broadcasts on the entire network. The best way to combine the advantages of both is to promote regional culture in second and third-tier cities through integrated media, as suggested by this. This study has the potential to provide an optimization strategy for promoting and disseminating regional culture in second and third-tier cities, which has significant strategic value.