The article theoretically substantiates the foundations of the professional development of primary school teachers in the system of methodical work of institutions of general secondary education, in particular, the definition of the concept «professional development of primary school teachers in the system of methodical work of institutions of general secondary education» is specified, which we understand as a managed dynamic process, which is inherently aimed at achieving a high level of professional development and develops according to scientific principles and approaches in specific pedagogical conditions, with the use of developed and adapted learning models in accordance with the requirements of the digital society, the concept of the New Ukrainian School, updating the system of methodical work and crisis conditions. Recommendations are given for the purpose of positive dynamics of professional development of primary school teachers in the methodical work system of general secondary education institutions.