Social media platforms are instrumental in helping tourism destinations project their tourism imaginaries to potential tourists. In light of this, this study refines a multimodal evaluative semiotic framework to understand how the Xizang Autonomous Region's (hereafter Xizang) tourism imaginaries are communicated via verbal and visual semiotic resources on mobile social media, i.e., Douyin. Analyzing 340 short videos from the official account of Xizang, we discerned seven distinctive attributes characterizing its tourism imaginaries. These encompass abundant natural resources, a wealth of historical and cultural heritages, authentic and immersive encounters, stable and supportive governance by the Chinese government, portrayal as a land of sanctity and healing, exceptional warmth and hospitality, and firm commitments to environmental sustainability. These multifaceted tourism imaginaries reflect the contemporary societal dynamics in the era of "nèi juǎn" (involution) of China's and Xizang's unique sociocultural and political contexts. The study's findings could guide marketing efforts and support sustainable growth in tourism, offering insights for branding in Xizang and similar ethnic destinations.