<p>Differences in cultural and social contexts lead to differences in the thoughts and expressions of social media users, which in turn lead to some natural and interesting differentiation phenomena. Taking the cultural sanctions against Russia as a case, this study analyzed public stance, opinion topics, and public sentiment of relevant posts and comments on X (formerly Twitter) and Weibo, and conducted a comparative analysis of the impact of cultural differences in information exchange. It was found that there were significant differences in the distributions of public stance and public sentiment, which could be related to cultural and social differences. In terms of public opinion topics, the two platforms reflected the spirit of individualism and collectivism in Western and Eastern cultures respectively. In addition, the forwarding networks also showed different network structure characteristics, with opinion leaders on X being relatively decentralized and having little influence differences among each other, while opinion leaders on Weibo were relatively centralized and had greater individual influences. This study demonstrates the importance of considering cultural factors in opinion analysis. The findings can help analyze public opinion in complex social media environments and provide a reference for management agencies in different cultural contexts to formulate more effective strategies for monitoring and guiding public opinion in major events.</p>