Abstract: This study explores the utilization of Grammarly by senior English Language majors at Nam Can Tho University during their graduation project writing. It aims to understand how these students leverage the application and the reasons for their choice. Employing a qualitative and quantitative approach, the research involved 50 fourth-year students from the Faculty of Foreign Languages at Nam Can Tho University. The findings reveal a strong consensus among participants regarding Grammarly's effectiveness in enhancing graduation project writing. Six core functionalities emerged as most frequently employed: grammar, spelling, and punctuation correction; vocabulary suggestions; sentence structure and writing quality improvement; tone adjustments; plagiarism detection; and draft storage. Error correction, particularly grammar, spelling, and punctuation, proved to be the most commonly used feature, while plagiarism detection and draft storage saw the least utilization. Furthermore, the findings highlight several key advantages of Grammarly for EFL students. Cross-platform compatibility emerged as a significant strength, allowing students to work seamlessly across mobile and laptop devices. This user-friendliness, combined with Grammarly's robust grammar and writing suggestions, fostered a sense of confidence in their writing proficiency. The detailed rationales provided for flagged errors facilitated comprehension and demonstrably minimized grammatical transgressions within their academic work. Furthermore, They also agreed that Grammarly saves time waiting for professors to verify assignments and instantly saves their work if the Internet is down. In conclusion, the study suggests that Grammarly functions as an effective and efficient online grammar checker, demonstrably supporting English as a Foreign Language (EFL) students throughout the graduation project writing process.