This writing aims to determine the function of Linguistics in English Language Teaching. It will discuss how important linguistics in English language teaching is. It uses the literature review method or called library research. In collecting the data, it uses the descriptive method and comparison method. From the finding, it can be concluded that linguistics pays attention to its function in teaching. Linguistics and language teaching are closely related to each other. This is because language teaching goes hand in hand with language growth. How is it possible that a language teacher can practice language skills if he does not master linguistics itself, how can he train writing skills if he does not master spelling, morphology, syntax, sem...