A growing body of research has examined the incorporation of English as a Lingua Franca (ELF) into Second Language (L2) instruction in various settings. Despite pedagogical innovations in L2 classrooms, little research has embodied retrospective explorations of the impact of ELF interventions with concrete instruments to measure the exact change in learners' attitudes, awareness, and knowledge. This study investigated how the ELF intervention can be integrated into an L2 classroom at a university to engage pre-service teachers in L2 reading and to increase their ELF awareness. Participants were divided into an experimental group (n = 35) and a control group (n = 26). The experimental group underwent a 12-week ELF intervention, including ELF awareness-raising readings and discussions in the Reading Skills course. The control group received instruction based on the Reading course content. This study adopted a collective case study design using the data from reading comprehension tests, reflection papers, focus group interviews, and an open-ended questionnaire. The results revealed that the experimental group outperformed the control group in L2 reading comprehension. The ELF intervention had a significant impact on the experimental group's conceptualizing of the ELF paradigm, developing attitudes, raising linguistic and cultural awareness, and increasing L2 reading motivation.