Introduction. Vaccination - the greatest achievement of mankind in the fight against infectious diseases. Immunization is the most common medical intervention, so the quality and safety of vaccines are special requirements. Identification, registration and investigation of adverse events following immunization are necessary to ensure its security and commitment of the population to be vaccinated. Objective: Optimize registration, investigation of UR after the immunization. Materials and methods: In April 2016 the Republic of Tatarstan Department staff vaccination WHO European Office conducted an audit of WHO for organizing immunization. In preparation for the audit, in order to create an action plan to improve the system for recording and investigation of adverse reactions (AR) analyzed 711 reports of AR, the final acts of the investigation AR, other medical documentation received by the Republican Centre for Immunoprophylaxis of Ministry of Healthcare of Tatarstan and notices received in the information database The Information and Methodological Center for Expertise, Accounting and Analysis Means of Medical Purpose in 2013 - 2016 Results and discussion In the Republic of Tatarstan approved the form of the identification message (suspected) unusual reaction, post-vaccination complications (suspect) as a result of immuno-biological drugs and the act of investigation of unusual reactions (suspected), post-vaccination complications (suspect) as a result of immunobiological drugs To consideration all cases of adverse reactions following vaccination was created Republican immunological сommission. Most of the reports (99%) came from the medical institutions of the Republic of Tatarstan, while only 1% of the messages were recorded by pharmaceutical companies. In most cases (98%) of UR after immunization observed in children aged 1 to 7 years. Significantly more AR were observed after immunization drugs belonging to the National calendar of preventive vaccinations, they accounted for 99.1% (705 cases), (p < 0.05). A significant number of UR associated with common disorders in health, local manifestations of vaccine introduction. Of the major UR met defeat of various organs and systems, but often observed manifestations of the nervous and cardiovascular systems. The group of major AR from the immune system have been included 2 (0.28%) cases of urticaria and anaphylactic shock in one patient, which was 0.1%. Lymphadenitis detected in 3 (0.4%) cases. Less rest fixed haematological disorders. Only 72.9% of the cards, notices have been filled in full Conclusions The Republic of Tatarstan is actively working to improve the accounting and investigation of adverse post-vaccination events. The National Centre for immunization was created, designed and approved the form of reports to detection (suspicion) unusual reaction, post-vaccination complications (suspicion) as a result of immuno-biological drugs, as well as the act of investigation of these phenomena. To consideration all cases of adverse reactions following vaccination was created Republican immunological commission. It was found that the largest number of AR occur when the vaccines included in the National calendar of preventive vaccinations. Most vaccines after application AR are not serious AR (96.5%), a major amount of which is connected with common disturbances in health status and local manifestations in administration Revealed insufficient activity of health professionals in accounting and registration of all AR that requires the provision of a wider information to health workers and parents on this issue. An important element of optimization work on accounting, registration AR is the actualization of the existing normative legal documents regulating the work of this section.