Introduction. Dental caries are the most common affection of the human population, at the same time, the mechanism by which some people are carioreceptive, and others remain free of caries, is of interest to researchers in the field.  Aim of the study. asseassing the level of immunoglobulins in oral fluid and blood serum and highlighting their influence on the susceptibility of children to dental caries.  Materials and methods. In the case-control study 162 children, aged between 7 and 18 years have been examinated. In the research group (L1) were included 81 children with severe carious activity, and the control group (L0) was made up of 81 caries-free children. Also, were evaluated dental caries prevalence indexes (IP) and indices of caries experience (dft, dfs, DMFT and DMFS). Was identified acidogenic bacterial plaque, concentration of the Streptococcus mutans in saliva, dental biofilm and in salivary pH with the use of standart kits GC. Complex assessment of caries risk was done using Software Cariogram. Immunoglobulin level in oral fluid (OF) andblood serum was determined by the immunoenzymatic method of analysis (Vectior-Best, Russia). The study was conducted in accordance with ethical requirements, with the written consent of the children’s parents or legal representatives. Analysis of statistical data, using parametric and nonparametric tests, was done using Microsoft® Excel® 2013 programs with the help of the function and of these programs.  Results. In children in group L1 there was a significant decrease in the level serum IgA, IgG, IgM and OF sIgA, IgA, IgG, being in reverse with the number of strains Streptococcus mutans in saliva, dental biofilm and indices of caries experience.  Conclusions. significant decrease in immunoglobulin levels in oral fluid and blood serum found in carioreceptive children is one of the important factors of carious risk and an unfavorable indicator of aggressive evolution of dental caries, which must be considered when planning individualized preventive measures.