This study investigates the role of speaking the Jing language in the contemporary context of China's active engagement with Vietnam. Based on the fieldwork conducted in Dongxing Guangxi in January 2024, the study shows that the Jing language plays an important role in both maintaining the cultural heritage as pride and empowering the educational and employment trajectories as profit. More importantly, the capacity of speaking the Jing language can contribute to the social and medical communication between China and Vietnam. This can be manifested in terms of cultural communication with Vietnam and medical treatment for Vietnamese migrants. However, speaking the Jing language as pride is not always consistent with speaking the Jing language as profit. The internal differentiation within Vietnamese varieties may cause communication barriers for Jing speakers. The limited development of the Jing language also creates another layer of communication challenges for Jing people engaging in professional practices. How to mobilize the Jing language to facilitate the bilateral communication between China and Vietnam deserves our attention for future studies. The study has enriched the scope of the studies on language planning and policy in the borderlands. The study can shed lights on implementing language policy in China's border provinces and provide practical implications to facilitate the political and economic communication between China and other neighbouring countries for border prosperity and border stability.