This systematic literature review examines how explicit and implicit vocabulary instruction impacts upper-secondary English as a foreign language (EFL) students’ reading comprehension and vocabulary growth. To find out the impact of vocabulary instruction, I will investigate the benefits explicit and implicit vocabulary instruction has on students’ reading comprehension and vocabulary growth. This study aims to find how teachers in Sweden can improve students’ reading comprehension and vocabulary knowledge with the help of vocabulary instruction. The research question is “What impact does explicit and implicit vocabulary instruction have on upper-secondary EFL students’ vocabulary growth and reading comprehension?”. Search terms for the electronic databases were vocabulary instruction, vocabulary growth, and reading comprehension. The studies used for this literature review were categorized into three common themes: The impact of explicit vocabulary instruction on reading comprehension, the impact of implicit vocabulary instruction on reading comprehension, and the impact of explicit and implicit vocabulary instruction on vocabulary growth. All studies reported different outcomes, this literature review summarized the results in one. The outcome is that both implicit and explicit vocabulary instruction are valuable in education in different ways. These findings aim to allow teachers to implement more explicit and implicit vocabulary instruction in Swedish EFL classrooms for future projects with the aim for students’ vocabulary growth and improving their reading comprehension.