Abstract <p>The individual development of most species of lepidopteran miner larvae is associated with one plant specimen. The development of all permanent miners is limited to one leaf, and the development of most facultative miners is limited to one canopy. Unlike a free-living phyllophage, the leaf miner larva cannot change the host plant, for example, if there is a shortage of food due to overpopulation. This determines the existence of mortality factors dependent on population density: both through intrapopulation competition of larvae and through the physiological state of the host plant. Among the representatives of the third trophic level, parasitoids are of greatest importance for the population dynamics of mining lepidopterans. The species diversity of miner parasitoid complexes among phytophagous insects is the highest. The functioning of the parasitoid complex is associated with structural and functional transformations over time. The mortality of larvae from pathogens is low.</p>