The future careers of students aged 15 to 24 are more or less affected by the school's course settings and majors, and students often have such problems that they have to choose some courses or majors. As a result, this phenomenon often comes up with gender inequality, which leads to occupational segregation. This study explored the reasons for students' choices of majors and courses. This research can help scholars better understand the considerations for students choosing majors and courses. This article analyzed 27 articles selected from Google Scholar. In a conclusion, the study found that different countries have different courses and majors to let students separate from each other by gender. Furthermore, students themselves will choose different courses or majors because of some personal factors and environmental factors like levels of competence, self-efficacy, students' vocational interests, and family reasons.