The Article is devoted to an actual problem of modern public Healthcare — Pneumococcal infections and possibilities of their prophylaxis. Background. To develope the effective and safe specific prevention method of pneumococcal disease in children of risk groups with the use of conjugated and polysaccharide-based vaccines. Materials and methods. 285 children of both genders aged from 6 months to 5 years old with various deviations in health status and risk factors of development of invasive pneumococcal disease were included in the study. Children from the main group (n=218) were immunized by the seven-valent pneumococcal conjugate vaccine (PCV7), part of children (n=31) were primary vaccinated by PCV7 later and received a boost dose of polysaccharide vaccine (PPV-23), children in the control group (n=36) were once immunized by PPV-23. Safety, clinical and immunological effectiveness of various schemes of vaccination were evaluated. Results. Frequency of adverse events to the introduction of PCV7 such as fever were up to 6.4%, local reactions — 4,6%. The majority of children (87—89%), immunized with PCV7 had elevated level of specific antibodies in more than 3 times compairing to the control group. In children vaccinated with PCV7, the number of pneumonia cases decreased to 6.8 times, acute average otitis — to 3,5 times, ARD — to 1,3 times.