PURPOSE: to check the importance of non-verbal communication for teachers in the exercise of their professional activities. METHODS: this research was conducted during the period from March to May, 2008. The studied population was made up of students from the two under-graduation courses the (Biological sciences and speech therapy). They were chosen randomly, 63 students, regardless of gender or age. RESULTS: data obtained showed that, regardless of their training (whether or not speech therapist), everybody considered that the non-verbal communication of the teacher is an important factor in the transmission of messages. CONCLUSION: the research showed that the investigated students and teachers evaluated the non-verbal communication as important for the effectiveness of interaction and can interfere in the performance of teachers in the classroom.