Abstract : This thesis, based on a socio-cognitive approach, deals with the professional training of student teachers in French agricultural education during their practical work experience. The main objective is to demonstrate that the student teacher's social interaction with his academic advisor allows him to use and develop his professional knowledge relating to practical matters and also to develop a feeling of professional efficiency. Based on a qualitative analysis this study presents the results of an investigation of seven students and six academic advisors. An empirical analysis indicates that discussions between the academic advisor and the student teacher affect the teaching methods of the student. This study also highlights the importance of such verbal and nonverbal communication between the academic advisor and the student teacher on the student's belief in his own efficiency. In constructing a typology of the professional's knowledge, it isshown that the students build and use teaching knowledge (scientific knowledge often called theoretical epistemic knowledge) and teaching ability (action-based knowledge often called practical phronesis knowledge). The linking of professional knowledge and social learning prompts us to propose a model of the socio-cognitive aspect of professional training during the student teacher's practical work experience.