The relevance of the subject is conditioned by the changes in approaches to professional training of qualified specialists based on the establishment of a correlation between psychological readiness, professional thinking, and further activities within the chosen specialisation. The purpose of the study is to analyse the process of forming professional thinking of future border guard officers under the influence of the author’s development programme. To achieve this purpose, a number of empirical research methods were used, including surveys and questionnaires, as well as the Pearson statistical criterion. The study presents the results of an experimental review of the programme for developing professional thinking of future border guard officers. A diagnostic study of the level of completeness of cadets’ professional thinking was carried out according to certain criteria (cognitive, need-motivational, operational) and levels (high, average, low). The existence of problems in the development of professional thinking of future border guard officers is confirmed and the absence of a significant difference in the conditions of groups according to certain levels and criteria of completeness is confirmed. To confirm the validity and uniformity of the control and experimental groups, they were tested using the Pearson statistical criterion. External influence on the studied experimental groups is carried out by a complex of developed tools of the author’s programme for the development of professional thinking. Positive changes (at least 95%) in the completeness of the corresponding components of cadets’ professional thinking of all groups are experimentally substantiated. The value of the research is determined by the confirmation of the author’s methodology effectiveness for the development of professional thinking, according to which it is possible to introduce it in related specialisation of Ukrainian higher educational institutions in the future