In recent years, the integration of artificial intelligence (AI) into educational practices has gained significant attention, with AI-powered tools like ChatGPT being widely adopted for enhancing learning experiences. This study aims to fill in the knowledge gap by the acceptance and use of ChatGPT among Chinese students in English-medium instruction (EMI) higher education programs in Macau and its correlation with foreign language anxiety (FLA). The research found that students exhibit high acceptance and diverse usage patterns of ChatGPT, and students widely accept and use ChatGPT, leading to substantially lower FLA levels. Regression analysis shows that frequent use of ChatGPT is a predictor for reduced FLA alongside perceived usefulness, ease of use, and positive attitudes towards the tool. These results suggest that ChatGPT can be used to improve learning experiences and reduce language anxiety in the course content of EMI programs and offer reasonable lessons for educational practices. This study provides valuable insights into the potential of AI tools to transform language education and supports the integration of technology to foster better educational outcomes.