The goal of genre-based instruction is to prepare students for success by continuously developing their English reading proficiency and expertise, allowing them to excel at a higher level. Genre-Based instruction "GBI" refers to teaching language based on the results of genre analysis in written and spoken form. This study examined the application of genre-based instruction in reading and comprehension classes in polytechnic universities in China. A mixed approach was adopted to fulfil the aim of this study, including different data collection approaches, such as questionnaires, quizzes, and semi-structured interviews. The quantitative study involved 100 students (control group: n = 50, experimental group: n = 50). Meanwhile, interviews were conducted with ten students from the experimental group in the qualitative study. The study findings demonstrate that genre-based instruction could improve students' reading proficiency and support the reading lessons in particular genres, contributing to significant practical implications. Students in the experimental group used headings, diagrams, and other information to predict the text content before reading, identified detailed information through scanning and searching, and summarised the main idea of passages and articles through genre teaching. Resultantly, students' reading efficiency improved, allowing them to quickly grasp the main idea of the text and correctly answer different questions, such as reasoning, judgment, and main idea.