Introduction.At present, the practice of training special education teachers/rehabilitators includes a diagnostic activity and related competencies as a basis for exploring the capabilities of children within the development process. The theoretical and practical content of diagnostic competence directly affects the quality of graduate training, determining its professional value and ability to work in varying educational and rehabilitation conditions. The relevance of the research problem is due to the search and development of standardised approaches to the training of specialists of the Higher School and the need to update the content of theoretical and practical knowledge in the field of diagnostic competence on the basis of contemporary requirements for this type of activity. The aim of the research is to study the diagnostic competence of students, teacher-speech pathologists and the description of the content of the pedagogical context in the aspect of knowledge, skills and mastery. Materials and Methods. The research sample consisted of 112 people from two professional groups: students and special education teachers. Research methods: direct questioning, cross-questioning, conversation (using the self-assessment scale), ranking the results of the questionnaire by index, graphic processing of information, interpretation of the results of the questionnaire for statistical data processing was used cluster analysis of the k-means Statistica 10.0. The questionnaire data were processed using Microsoft Office Excel (Excel). Results. An empirical confirmation of the hypothesis, that determining the level of development of diagnostic competence within the pedagogical context will make it possible to clarify the “problem” areas in the knowledge and skills used by teachers in the diagnostic procedure, was obtained. There were 3 clusters of respondents with different levels of diagnostic competence formation, the second of which, having diagnostic competence at the stage of formation, was most numerous. For all clusters, difficulties in understanding the methodological positions of the diagnostic procedure were r evealed, including a lack of knowledge on developmental diagnostics within the pedagogical field and a lack of clear differentiation in the selection of basic algorithms for diagnostic actions. Discussion and Conclusion. The predominance of the cluster having diagnostic competence at the stage of formation indicates a need for the diagnostic competence programme to be updated. The research results can be used to develop content for the programme of diagnostic competence at all formation levels, which, from a practical point of view would be useful for improving the educational programme of the university and improving the quality of diagnostic procedures. The value of the research lies in its analysis of the substantive context of diagnostic competence, the systemic content of which reflects contemporary demands of the state and society regarding this type of activity and determines the vector of further research in terms of the development of the content of competency programmes based on the understanding of contemporary diagnostic activity requirements.