This research paper describes a mixed-methods study with a one group, pretest- posttest design that aimed to analyze the effects of writing reflective journals on the writing skills of 25 EFL sophomore learners. It also examined the participants’ perceptions of reflective journals as a learning strategy. The data were collected in two phases. In the first phase, a pre-test and a post-test were applied to gather the quantitative data. The researchers employed a writing assessment rubric to score the pre- and post-tests to assess the students’ EFL proficiency level. And in the second phase, participants were required to fill out an open-ended questionnaire of six questions to collect the qualitative data. It was demonstrated that reflective journals had a positive impact on the participants’ writing skills development and that they were perceived as a helpful learning strategy to boost English proficiency. These findings could help EFL students improve their metacognitive skills, which are required in the Ecuadorian curriculum.