With the ongoing improvement in higher education, the subject contest has received increasing attention as a crucial means of fostering talent development. As important participants in the subject contest, undergraduate students face many problems during the contest process, such as low recognition of the subject contest, lack of confidence in par-ticipating in the subject contest, a single channel of access to information regarding the subject contest, and poor atmosphere for participating in the subject contest, which lead to suboptimal effectiveness of student participation in the subject contest. How to better promote undergraduate students’ participation in the subject contest has also emerged as a significant research topic in the new era of education. Based on the theory of planned behavior and the theory of social practice, combined with the characteristics of undergraduate students participating in the subject contest, the influencing factors of undergraduate students’ intention to participate in the subject contest were identi-fied and a mechanism model of undergraduate students’ intention to participate in the subject contest was constructed in this study. Taking undergraduate students majoring in engineering management as an example, reliability and validity testing, factor analysis, and structural equation model verification were conducted on 375 valid data by SPSS and AMOS software. The findings indicate that attitudes towards participating in the subject contest, subjective norms, employment or academic advantages have a significant positive impact on the intention of undergraduate students to participate in the subject contest, while perceived behavioral control, a favorable school competition atmosphere, and individual characteristics of undergraduate students have little effect on their intention. On this basis, three sugges-tions were proposed to promote the participation of undergraduate students in the subject contest, including strengthening the education and training of undergraduate students and improving students’ attitude to participate in the subject contest; expanding the publicity scope of participating in the subject contest and promoting students’ subjective norms to participate in the subject contest; improving the system of participating in the subject contest and highlighting the future advantages of students’ participation in the subject contest.