This study examines students’ perceptions of the Guided Use of Machine Translation (GUMT) model and their perceptions of GUMT’s impact on their foreign language (FL) writing. Adapted from O’Neill (2016, 2019b), GUMT model activities were developed and implemented in an upper-elementary Korean as a FL course at a large southwestern U.S. university. At the beginning of the semester, students received an instructional session on how to use machine translation (MT) effectively as the first step of GUMT. The session included 1) the potential strengths and weaknesses of two online Korean MT platforms, Google Translate and Papago; and 2) the combined use of other online resources (e.g., image and news searches) to enhance students’ awareness of pragmatic issues related to MT output. Throughout the semester, students applied the GUMT model to writing assignments and wrote reflections on their GUMT practice. Students also received continuous feedback from instructors on MT use. Analyses of pre- and post-surveys and students’ reflections indicate that the GUMT model played an important role in fostering MT use strategies and improving students’ confidence and self-perceptions of their fluency in FL writing.