Student Centered e-Learning Environment (SCeLE) has substantial roles to support learning activities at Faculty of Computer Science, Universitas Indonesia (Fasilkom UI). Although it has been utilized for about 10 years, the usability aspect of SCeLE as an e-Learning system has not been evaluated. Therefore, the usability aspects of SCeLE Fasilkom UI as a learning support system is not well-acquainted yet. Accordingly, the researchers are in need of conducting a usability evaluation in order to propose a set of recommendation for SCeLE usability improvement, based on usability evaluation reflecting both students and lecturers experience as user. In this present research, the usability testing was conducted for SCeLE, targeting learning activities underwent by undergraduate students at Fasilkom UI, in the form of blended mode online learning. The data collection stage in the usability testing was performed by distributing questionnaires to students and interviewing several lecturers and students. The collected data were then analyzed and interpreted in order to obtain usability problems and solution alternatives. The quantitative data were analyzed using the mean as a reference, while the qualitative data were analyzed using theme-based content analysis. Data interpretation was performed by determining how to handle each kind of data based on its theme, and classifying each of the identified usability problem referring to its severity rating.