The research aims to give some analysis toward the function of lexicogrammatical which was featured by the students to structure biography text. The use of lexicogrammatical within writing a text is substantial since this part highlighted the interconnectedness of vocabulary (lexis) and syntax (syntax) is stressed in systemic functional linguistics (SFL) (grammar). To realize this topic, the researcher administrated both documentation and students’ interview which were distributed to the students of SMA Negeri 14 Semarang in grade X. The researcher observed five students where they came from class science 1-5. Through both documentation and interview section, the result showed that students were aware to employ those application of lexicogrammatical although a few mistakes were found. This research then suggested1that the pupils who learnt this genre must be evaluated through personal reading and practices as well as teachers’ facilitation so that the inaccuracy of language feature could be minimalized.