Introduction. The article describes the process of development and the results of validation of the “Professional competences of a higher school teacher” research methodology. The theoretical construct of the methodology was developed theoretically and empirically, with consideration to the principles of integrative and competence-activity approaches, and understanding of the system of professional competences. Self-organisational, informational, interactive and multicultural competences as well as readiness for professional pedagogical activity are proved as the main components of the suggested system of leading professional competences of a higher school teacher. Methods. The operationalisation of the methodology from 2022 to 2025 is described. The article presents the validation results of the final version of the methodology based on an extended sample of 366 teachers of educational institutions of the Ministry of Internal Affairs of Russia in different federal districts aged from 25 to 55 years with teaching experience from 1 to 25 years, among whom 42,1% are men and 57,9% are women. The reliability of the methodology was tested using Cronbach’s alpha coefficient. The methodology was tested for content, competitive, construct and predictive validity using correlation analysis, confirmatory factor analysis, linear regression analysis with calculation of regression equations. The empirical data were processed using SPSS 26.0, IBM SPSS AMOS 26 Graphics and Excel software package. Results. The validity and internal consistency of the methodology are evidenced by the data obtained by applying Cronbach’s alpha coefficient, expert evaluation method, correlation analysis, confirmatory factor analysis, and linear regression analysis.