It remains unquestionable that learning a language such as English through online mode may have transformative impacts on students’ motivational process. Grounded from the rationale, this study explored EFL students’ (de)motivating factors in integrating e-mentoring methods during academic writing projects. Thirteen selected university students with different demographic variables (i.e., grade, gender, university, age, language proficiency) attended multiple interviews, focus group discussions, and classroom observation as data collection methods. The data were analysed through the integration of IDEEAS framework, consisting of Inclusion, Design, Engagement, Evaluation, Assessment, and Support phases and a descriptive statistical analysis. The findings are twofold. First, e-mentoring motivated EFL students to engage with academic paper writing as it effectively reduced cultural and linguistic barriers (i.e., through online tutorials, games, or discussion), promoted always-on communication (i.e., through synchronous and asynchronous modes), and relied on process rather than product (i.e., through dialogic syllabus). Nevertheless, e-mentoring remained demotivating for the students as it concerned with verbalised communication, threatened face-to-face interaction, and caused them to rely on online culture. This study implies that university stakeholders, mentors, or supervisors have to integrate e-mentoring into English learning curriculum and facilitate online learning procedures systematically. In short, motivating and demotivating factors in e-mentoring process remain critical as academic paper writing cannot be successfully engaged with online meeting. The e-mentor has to implement particular strategies by intensively utilising online apps to increase effective communication and overcome drawbacks during the academic writing project.