Transnational online education has become an emerging trend in promoting academic collaboration and exchange in higher education during and after the pandemic. Guided by the learning ecology framework, we conducted concurrent mixed methods research by distributing an online survey to Chinese students (N=51) to collect quantitative and qualitative data. This helped us deeply understand their experiences and perceptions of a cross-cultural online learning environment in the United States. We applied multiple regression and thematic analysis to analyze the data. The merging of both types of data analysis indicated the confirmation of the importance of discipline-based English learning environments, the transformation of online learning practices, the insufficiency of student-to-instructor interactions, discordance of technological self-efficacy and the disadvantages of technology-assisted instruction, and discordance between the usefulness and difficulties of learning activities and assessments. We further discussed appropriate strategies and techniques to promote online teaching and learning excellence in transnational distance education.