Introduction. A significant role in the development of continuous professional education of teachers is played by scientific and methodological support of teaching staff as a complex of interconnected targeted actions and events aimed at providing comprehensive assistance to the teacher in solving emerging difficulties, contributing to his development and self-determination throughout his professional activity. The purpose of the study is to identify and substantiate organizational and pedagogical conditions that contribute to the effective management of the development of a regional system of additional professional education for teachers. Materials and methods: theoretical analysis, generalization, modeling, questionnaires, testing, expert assessment method. Results, discussion. The organizational and pedagogical conditions for scientific and methodological support of teaching staff in the context of the regional system of additional professional education have been identified, scientifically substantiated and experimentally confirmed: the creation of a unified information and educational space for scientific and methodological support of teachers by means of network interaction mechanisms; design and implementation of individual educational routes that ensure the development of professional skills of teaching staff, taking into account the socio-economic characteristics of the region and the regional educational space; identification, systematization, selection and dissemination of effective regional mentoring practices; systematic assessment of the effectiveness of scientific and methodological support for teaching staff in the regional system of additional education. Conclusion: The effectiveness of the identified organizational and pedagogical conditions in the process of implementing the model of scientific and methodological support for teaching staff in the context of the regional system of additional professional education was confirmed by the results of the pedagogical experiment we conducted. 2178 teachers from 249 educational organizations of the Republic of Mari El took part in the experimental part of the study. The absolute increase in the number of teaching staff who received targeted methodological support in the development and implementation of individual educational routes was 5 %, those provided with personal support in the process of improving their qualifications and pedagogical skills in the implementation of individual educational routes was 100 %, young teachers involved in various forms of support and support, from the total number of young teachers 98.5 %. Positive dynamics were noted for all indicators of the organization of advanced training of teaching staff within the framework of the implementation of priority federal programs.