The application of the language proficiency scales (LPS) in education validates its function, as it can explore the value in-depth. However, little systematic research on applying LPS has been conducted due to the complex intertwining of stakeholders and a lack of theoretical framework and practical approaches. Adopting the framework proposed by Y. Jin and Jie (2020), this study explored how the Common European Framework of Reference (CEFR) and China's Standards of English (CSE) were used and impacted various stakeholders in the education context. The literature search was taken from WoSCC, Scopus, and CNKI from 2018 to 2022. Qualitative content analysis was used for systematic review. Results showed that policymakers used LPS in education policy guidance; teachers applied them as the benchmark of diagnostic assessment to get accurate language profiles of students and create new approaches to teaching; students used them as goal-setting guidance and self- or peer assessment criteria to track progress; test developers aligned them with tests to obtain reliable results; curriculum designers tailored descriptors and scales from CEFR to develop new curricula, align, or revise the existing ones; researchers used LPS as references to develop new rubrics, frameworks and assessing models. This study could provide insight in scientific application of LPS. However, it focused mainly on the CEFR and CSE with a framework for exploring the impact of language testing. Studies containing more scales and theorizing the framework of aftereffects of LPS should be encouraged.