In the context of this study, the researchers aimed to investigate the level of understanding of English-majored students at Saigon University regarding the 2018 General Education English Curriculum at upper secondary level. Through a mixed-methods research design involving surveys of 71 students and interviews with 8 students, the researchers found that the students had a fairly good understanding of the views of curriculum design, requirements to be met, and assessment of learning in the 2018 General Education English Curriculum at upper secondary level. However, the students still lacked in-depth knowledge in areas such as curriculum objectives, educational contents, and educational methodology. The findings suggest that institutions offering TESOL programs should consider adjusting or supplementing their courses related to the new curriculum to better prepare students with the necessary knowledge for teaching practices in the future.