In the era of globalisation with the rapid development of science and technology, the use of Information and Communication Technology (ICT) for language learning has become one of the prominent challenges in language teaching, including in the Indonesian context (Kariman 2005). This study aims to investigate how online portfolios as part of ICT tools could be used to facilitate the learning of EFL writing in an Indonesian EFL writing class. This study is concerned with my own teaching experiences due to the growing demand for teachers’ competence to integrate technology for the purpose of facilitating students’ learning. The implementation of the online portfolio over one semester was examined through action research. Students’ experiences in learning EFL writing using the online portfolio were explored with regards to their writing skills development, learner autonomy and motivation. In addition to the action research, the study drew on case study and ethnographic approaches. As for methods for generating data, this study involved questionnaires, interviews, teacher’s reflective journals, and an analysis of online portfolio entries. The findings of the study show that the online portfolios have been beneficial in developing students’ EFL writing skills. Concerning learner autonomy, the online portfolios have facilitated students’ to develop their metacognitive knowledge, metacognitive strategies, social strategies, and critical thinking. As for students’ motivation, the findings of the current study suggest that the use of a blog as the online portfolio platform and the online portfolio elements comprising self-revising, feedback activities and reflection enhanced students’ motivation to learn how to write. They achieved this by raising students’ expectation of success in their learning, making students feel comfortable in working with their writing tasks, and challenging students to write to a higher standard as their writings were published online, read and commented on by others. Moreover, the study suggests that the success of the online portfolio implementation in facilitating students’ learning of EFL writing requires teachers’ understandings of their own roles as well as their willingness to undertake and develop their roles as facilitators in an e-learning environment.