There is scarce evidence of publications pertaining to the phenomenon that a foreign teachers' language in fact is a language for specific purposes. In the field of (foreign) languages for specific purposes, traditionally linked to a vast variety of professional and academic domains, it seems that LSP teachers' language has not yet gained due attention. However, any FL or LSP teacher's language is used for professional, teaching purposes; yet it does not seem that FL teachers for specific purposes are aware of their teacher talk, either in class or conceptually. On the basis of classroom observation and semi-structured interviews among 17 Slovenian teachers of foreign languages for specific purposes this paper attempted to identify differences in the teacher talk used by them in class, and the level of their awareness of their own teacher talk. The results of the quantitative analysis indicate that there are some specific features in LSP teacher talk which led us to conclude that it could be identified and categorised as a separate LSP category. However, the related LSP teacher's awareness about their own teacher talk varied from highly profiled to absent, and there was a perceptible impact on working efficiency in the class. All discussed phenomena require further research.