Many educational researchers and teachers have agreed that language can be fostered in the context of science teaching. However, the effect of language fostering has depended heavily on teacher's perception. Recognizing the role of teaching (including Physics teaching) in language training will help teachers become conscious while designing teaching activities, contributing to promoting cognitive activities of students. Therefore, the purpose of the study was to identify teachers' perceptions to foster language in the context of physics teaching in Northern Vietnam, where many ethnic minority students study for whom Vietnamese is like the second language. A survey was used to collect the data from 64 physics teachers who taught in high schools. The differences in teaching experience and education background of physics teachers toward languages fostering were examined by the independent sample t-test and the one-way ANOVA. The obtained results show that (i) most teachers held a positive view about the importance of language of physics in teaching (ii) There were no statistically significant differences in the importance of language in teaching physics based on the education background of teachers; (iii) The novice teachers held a more positive perception than the experienced ones about the importance and signs of language in the student's physics learning process. These results would prove to be a valuable source of information for designing physics teaching activities for language fostering in mountainous areas of Vietnam.