In the context of global cultural integration and diversified ideological communication, college English teaching, as a core cross-cultural curriculum, undertakes the fundamental mission of moral education and ideological guidance. Ethnic border regions represented by Inner Mongolia face unique educational scenarios, where college English teaching needs to coordinate foreign language talent cultivation, ethnic unity inheritance and regional ideological security maintenance, placing higher demands on English teachers’ ideological literacy. This study conducted a questionnaire survey on 328 college English teachers from 9 universities in Inner Mongolia, covering comprehensive universities, science and engineering universities and ethnic universities. The survey data show that only 21.3% of teachers can organically integrate ideological education into daily language teaching; 74.7% of teachers lack systematic understanding of local grassland culture and ethnic unity education; 68.6% of teachers cannot accurately identify hidden ideological risks in foreign textbooks; and 82.0% of schools adopt unified general training without targeted ethnic regional courses. In view of the dual attributes of foreign language disciplines (open and culturally permeable) and the particularity of multi-ethnic border education, college English teachers in ethnic areas commonly suffer from disjointed professional teaching and ideological education, insufficient cross-cultural ideological discrimination capability and a lack of localized educational awareness. Based on the three-dimensional integration framework covering foreign language disciplinary attributes, ethnic regional characteristics and international educational background, this study adopts literature analysis, questionnaire survey and classroom observation to systematically investigate the current situation and practical dilemmas of English teachers’ ideological literacy in Inner Mongolia’s universities. By clarifying the internal logical connection between the three-dimensional theoretical framework and teachers’ literacy cultivation, this paper constructs localized, targeted improvement paths. The research results can optimize the ideological education system of foreign language disciplines, enhance teachers’ cultural communication and ideological risk prevention capabilities, and provide practical references for consolidating the ideological security defense line of ethnic border areas.