The paper studies the content and inner structure of the instrumental component of professional identity of future technical specialists. Different models of the structure of professional identity of future specialists, teachers and medical psychologists are analysed. Ternary structure of the professional identity of a future technical specialist is proposed. Each component of the professional identity is viewed in terms of fourth-year students of mathematics. The list of knowledge (special or orienting and nonspecific or culturological), skills and abilities, which a higher technical school graduate should possess for the successful performance of professional tasks, is provided. The role of professional competencies in the context of the professional identity is determined. On the basis of theoretical analysis, the structure of professional competencies in terms of bachelors of mathematics is considered. Examples of instrumental and system, personal-social (personal, communicative and information) and special competencies, which are a part of professional competencies, are proposed. The role of formation of professional identity in the process of studying at a higher technical school is considered. The problems of professionalism of activity and competitiveness of a higher technical school graduate in the labour market are considered.